1 # This file is in the public domain, so clarified as of
2 # 2009-05-17 by Arthur David Olson.
4 # also includes Central America and the Caribbean
6 # This file is by no means authoritative; if you think you know better,
7 # go ahead and edit the file (and please send any changes to
8 # tz@iana.org for general use in the future). For more, please see
9 # the file CONTRIBUTING in the tz distribution.
11 # From Paul Eggert (1999-03-22):
12 # A reliable and entertaining source about time zones is
13 # Derek Howse, Greenwich time and longitude, Philip Wilson Publishers (1997).
15 ###############################################################################
19 # From Paul Eggert (1999-03-31):
20 # Howse writes (pp 121-125) that time zones were invented by
21 # Professor Charles Ferdinand Dowd (1825-1904),
22 # Principal of Temple Grove Ladies' Seminary (Saratoga Springs, NY).
23 # His pamphlet "A System of National Time for Railroads" (1870)
24 # was the result of his proposals at the Convention of Railroad Trunk Lines
25 # in New York City (1869-10). His 1870 proposal was based on Washington, DC,
26 # but in 1872-05 he moved the proposed origin to Greenwich.
28 # From Paul Eggert (2016-09-21):
29 # Dowd's proposal left many details unresolved, such as where to draw
30 # lines between time zones. The key individual who made time zones
31 # work in the US was William Frederick Allen - railway engineer,
32 # managing editor of the Travelers' Guide, and secretary of the
33 # General Time Convention, a railway standardization group. Allen
34 # spent months in dialogs with scientific and railway leaders,
35 # developed a workable plan to institute time zones, and presented it
36 # to the General Time Convention on 1883-04-11, saying that his plan
37 # meant "local time would be practically abolished" - a plus for
38 # railway scheduling. By the next convention on 1883-10-11 nearly all
39 # railroads had agreed and it took effect on 1883-11-18 at 12:00.
40 # That Sunday was called the "day of two noons", as the eastern parts
41 # of the new zones observed noon twice. Allen witnessed the
42 # transition in New York City, writing:
44 # I heard the bells of St. Paul's strike on the old time. Four
45 # minutes later, obedient to the electrical signal from the Naval
46 # Observatory ... the time-ball made its rapid descent, the chimes
47 # of old Trinity rang twelve measured strokes, and local time was
48 # abandoned, probably forever.
50 # Most of the US soon followed suit. See:
51 # Bartky IR. The adoption of standard time. Technol Cult 1989 Jan;30(1):25-56.
52 # http://dx.doi.org/10.2307/3105430
54 # From Paul Eggert (2005-04-16):
55 # That 1883 transition occurred at 12:00 new time, not at 12:00 old time.
56 # See p 46 of David Prerau, Seize the daylight, Thunder's Mouth Press (2005).
58 # From Paul Eggert (2006-03-22):
59 # A good source for time zone historical data in the US is
60 # Thomas G. Shanks, The American Atlas (5th edition),
61 # San Diego: ACS Publications, Inc. (1991).
62 # Make sure you have the errata sheet; the book is somewhat useless without it.
63 # It is the source for most of the pre-1991 US entries below.
65 # From Paul Eggert (2001-03-06):
66 # Daylight Saving Time was first suggested as a joke by Benjamin Franklin
67 # in his whimsical essay "An Economical Project for Diminishing the Cost
68 # of Light" published in the Journal de Paris (1784-04-26).
69 # Not everyone is happy with the results:
71 # I don't really care how time is reckoned so long as there is some
72 # agreement about it, but I object to being told that I am saving
73 # daylight when my reason tells me that I am doing nothing of the kind.
74 # I even object to the implication that I am wasting something
75 # valuable if I stay in bed after the sun has risen. As an admirer
76 # of moonlight I resent the bossy insistence of those who want to
77 # reduce my time for enjoying it. At the back of the Daylight Saving
78 # scheme I detect the bony, blue-fingered hand of Puritanism, eager
79 # to push people into bed earlier, and get them up earlier, to make
80 # them healthy, wealthy and wise in spite of themselves.
82 # -- Robertson Davies, The diary of Samuel Marchbanks,
83 # Clarke, Irwin (1947), XIX, Sunday
85 # For more about the first ten years of DST in the United States, see
86 # Robert Garland, Ten years of daylight saving from the Pittsburgh standpoint
87 # (Carnegie Library of Pittsburgh, 1927).
88 # http://www.clpgh.org/exhibit/dst.html
90 # Shanks says that DST was called "War Time" in the US in 1918 and 1919.
91 # However, DST was imposed by the Standard Time Act of 1918, which
92 # was the first nationwide legal time standard, and apparently
93 # time was just called "Standard Time" or "Daylight Saving Time".
95 # From Arthur David Olson:
96 # US Daylight Saving Time ended on the last Sunday of *October* in 1974.
97 # See, for example, the front page of the Saturday, 1974-10-26
98 # and Sunday, 1974-10-27 editions of the Washington Post.
100 # From Arthur David Olson:
101 # Before the Uniform Time Act of 1966 took effect in 1967, observance of
102 # Daylight Saving Time in the US was by local option, except during wartime.
104 # From Arthur David Olson (2000-09-25):
105 # Last night I heard part of a rebroadcast of a 1945 Arch Oboler radio drama.
106 # In the introduction, Oboler spoke of "Eastern Peace Time."
107 # An AltaVista search turned up:
108 # https://web.archive.org/web/20000926032210/http://rowayton.org/rhs/hstaug45.html
109 # "When the time is announced over the radio now, it is 'Eastern Peace
110 # Time' instead of the old familiar 'Eastern War Time.' Peace is wonderful."
111 # (August 1945) by way of confirmation.
113 # From Paul Eggert (2017-09-23):
114 # This was the V-J Day issue of the Clamdigger, a Rowayton, CT newsletter.
116 # From Joseph Gallant citing
117 # George H. Douglas, _The Early Days of Radio Broadcasting_ (1987):
118 # At 7 P.M. (Eastern War Time) [on 1945-08-14], the networks were set
119 # to switch to London for Attlee's address, but the American people
120 # never got to hear his speech live. According to one press account,
121 # CBS' Bob Trout was first to announce the word of Japan's surrender,
122 # but a few seconds later, NBC, ABC and Mutual also flashed the word
123 # of surrender, all of whom interrupting the bells of Big Ben in
124 # London which were to precede Mr. Attlee's speech.
126 # From Paul Eggert (2003-02-09): It was Robert St John, not Bob Trout. From
127 # Myrna Oliver's obituary of St John on page B16 of today's Los Angeles Times:
129 # ... a war-weary U.S. clung to radios, awaiting word of Japan's surrender.
130 # Any announcement from Asia would reach St. John's New York newsroom on a
131 # wire service teletype machine, which had prescribed signals for major news.
132 # Associated Press, for example, would ring five bells before spewing out
133 # typed copy of an important story, and 10 bells for news "of transcendental
136 # On Aug. 14, stalling while talking steadily into the NBC networks' open
137 # microphone, St. John heard five bells and waited only to hear a sixth bell,
138 # before announcing confidently: "Ladies and gentlemen, World War II is over.
139 # The Japanese have agreed to our surrender terms."
141 # He had scored a 20-second scoop on other broadcasters.
143 # From Arthur David Olson (2005-08-22):
144 # Paul has been careful to use the "US" rules only in those locations
145 # that are part of the United States; this reflects the real scope of
146 # U.S. government action. So even though the "US" rules have changed
147 # in the latest release, other countries won't be affected.
149 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
150 Rule US 1918 1919 - Mar lastSun 2:00 1:00 D
151 Rule US 1918 1919 - Oct lastSun 2:00 0 S
152 Rule US 1942 only - Feb 9 2:00 1:00 W # War
153 Rule US 1945 only - Aug 14 23:00u 1:00 P # Peace
154 Rule US 1945 only - Sep lastSun 2:00 0 S
155 Rule US 1967 2006 - Oct lastSun 2:00 0 S
156 Rule US 1967 1973 - Apr lastSun 2:00 1:00 D
157 Rule US 1974 only - Jan 6 2:00 1:00 D
158 Rule US 1975 only - Feb 23 2:00 1:00 D
159 Rule US 1976 1986 - Apr lastSun 2:00 1:00 D
160 Rule US 1987 2006 - Apr Sun>=1 2:00 1:00 D
161 Rule US 2007 max - Mar Sun>=8 2:00 1:00 D
162 Rule US 2007 max - Nov Sun>=1 2:00 0 S
164 # From Arthur David Olson, 2005-12-19
165 # We generate the files specified below to guard against old files with
166 # obsolete information being left in the time zone binary directory.
167 # We limit the list to names that have appeared in previous versions of
168 # this time zone package.
169 # We do these as separate Zones rather than as Links to avoid problems if
170 # a particular place changes whether it observes DST.
171 # We put these specifications here in the northamerica file both to
172 # increase the chances that they'll actually get compiled and to
173 # avoid the need to duplicate the US rules in another file.
175 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
178 Zone HST -10:00 - HST
179 Zone EST5EDT -5:00 US E%sT
180 Zone CST6CDT -6:00 US C%sT
181 Zone MST7MDT -7:00 US M%sT
182 Zone PST8PDT -8:00 US P%sT
184 # From U. S. Naval Observatory (1989-01-19):
185 # USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON
186 # USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30
187 # USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON
188 # USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30
189 # USA MOUNTAIN 7 H BEHIND UTC DENVER
190 # USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30
191 # USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO
192 # USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30
193 # USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST)
194 # USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT)
195 # USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W
196 # USA " 9 H BEHIND UTC APR 3 - OCT 30
197 # USA HAWAII 10 H BEHIND UTC
198 # USA BERING 11 H BEHIND UTC SAMOA, MIDWAY
200 # From Arthur David Olson (1989-01-21):
201 # The above dates are for 1988.
202 # Note the "AKST" and "AKDT" abbreviations, the claim that there's
203 # no DST in Samoa, and the claim that there is DST in Alaska and the
206 # From Arthur David Olson (1988-02-13):
207 # Legal standard time zone names, from United States Code (1982 Edition and
208 # Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names
209 # up to 1967-04-01 (when most provisions of the Uniform Time Act of 1966
210 # took effect), as explained in sections 263 and 261:
212 # United States standard eastern time
213 # United States standard mountain time
214 # United States standard central time
215 # United States standard Pacific time
217 # United States standard Alaska time
219 # Next, names from 1967-04-01 until 1983-11-30 (the date for
220 # public law 98-181):
221 # Atlantic standard time
222 # eastern standard time
223 # central standard time
224 # mountain standard time
225 # Pacific standard time
226 # Yukon standard time
227 # Alaska-Hawaii standard time
228 # Bering standard time
229 # And after 1983-11-30:
230 # Atlantic standard time
231 # eastern standard time
232 # central standard time
233 # mountain standard time
234 # Pacific standard time
235 # Alaska standard time
236 # Hawaii-Aleutian standard time
237 # Samoa standard time
238 # The law doesn't give abbreviations.
240 # From Paul Eggert (2016-12-19):
241 # Here are URLs for the 1918 and 1966 legislation:
242 # http://uscode.house.gov/statviewer.htm?volume=40&page=451
243 # http://uscode.house.gov/statviewer.htm?volume=80&page=108
244 # Although the 1918 names were officially "United States Standard
245 # Eastern Time" and similarly for "Central", "Mountain", "Pacific",
246 # and "Alaska", in practice "Standard" was placed just before "Time",
247 # as codified in 1966. In practice, Alaska time was abbreviated "AST"
248 # before 1968. Summarizing the 1967 name changes:
249 # 1918 names 1967 names
250 # -08 Standard Pacific Time (PST) Pacific standard time (PST)
251 # -09 (unofficial) Yukon (YST) Yukon standard time (YST)
252 # -10 Standard Alaska Time (AST) Alaska-Hawaii standard time (AHST)
253 # -11 (unofficial) Nome (NST) Bering standard time (BST)
255 # From Paul Eggert (2000-01-08), following a heads-up from Rives McDow:
256 # Public law 106-564 (2000-12-23) introduced ... "Chamorro Standard Time"
257 # for time in Guam and the Northern Marianas. See the file "australasia".
259 # From Paul Eggert (2015-04-17):
260 # HST and HDT are standardized abbreviations for Hawaii-Aleutian
261 # standard and daylight times. See section 9.47 (p 234) of the
262 # U.S. Government Printing Office Style Manual (2008)
263 # https://www.gpo.gov/fdsys/pkg/GPO-STYLEMANUAL-2008/pdf/GPO-STYLEMANUAL-2008.pdf
265 # From Arthur David Olson, 2005-08-09
266 # The following was signed into law on 2005-08-08.
268 # H.R. 6, Energy Policy Act of 2005, SEC. 110. DAYLIGHT SAVINGS.
269 # (a) Amendment.--Section 3(a) of the Uniform Time Act of 1966 (15
270 # U.S.C. 260a(a)) is amended--
271 # (1) by striking "first Sunday of April" and inserting "second
272 # Sunday of March"; and
273 # (2) by striking "last Sunday of October" and inserting "first
274 # Sunday of November'.
275 # (b) Effective Date.--Subsection (a) shall take effect 1 year after the
276 # date of enactment of this Act or March 1, 2007, whichever is later.
277 # (c) Report to Congress.--Not later than 9 months after the effective
278 # date stated in subsection (b), the Secretary shall report to Congress
279 # on the impact of this section on energy consumption in the United
281 # (d) Right to Revert.--Congress retains the right to revert the
282 # Daylight Saving Time back to the 2005 time schedules once the
283 # Department study is complete.
285 # US eastern time, represented by New York
287 # Connecticut, Delaware, District of Columbia, most of Florida,
288 # Georgia, southeast Indiana (Dearborn and Ohio counties), eastern Kentucky
289 # (except America/Kentucky/Louisville below), Maine, Maryland, Massachusetts,
290 # New Hampshire, New Jersey, New York, North Carolina, Ohio,
291 # Pennsylvania, Rhode Island, South Carolina, eastern Tennessee,
292 # Vermont, Virginia, West Virginia
294 # From Dave Cantor (2004-11-02):
295 # Early this summer I had the occasion to visit the Mount Washington
296 # Observatory weather station atop (of course!) Mount Washington [, NH]....
297 # One of the staff members said that the station was on Eastern Standard Time
298 # and didn't change their clocks for Daylight Saving ... so that their
299 # reports will always have times which are 5 hours behind UTC.
301 # From Paul Eggert (2005-08-26):
302 # According to today's Huntsville Times
303 # http://www.al.com/news/huntsvilletimes/index.ssf?/base/news/1125047783228320.xml&coll=1
304 # a few towns on Alabama's "eastern border with Georgia, such as Phenix City
305 # in Russell County, Lanett in Chambers County and some towns in Lee County,
306 # set their watches and clocks on Eastern time." It quotes H.H. "Bubba"
307 # Roberts, city administrator in Phenix City. as saying "We are in the Central
308 # time zone, but we do go by the Eastern time zone because so many people work
311 # From Paul Eggert (2017-02-22):
312 # Four cities are involved. The two not mentioned above are Smiths Station
313 # and Valley. Barbara Brooks, Valley's assistant treasurer, heard it started
314 # because West Point Pepperell textile mills were in Alabama while the
315 # corporate office was in Georgia, and residents voted to keep Eastern
316 # time even after the mills closed. See: Kazek K. Did you know which
317 # Alabama towns are in a different time zone? al.com 2017-02-06.
318 # http://www.al.com/living/index.ssf/2017/02/do_you_know_which_alabama_town.html
320 # From Paul Eggert (2014-09-06):
321 # Monthly Notices of the Royal Astronomical Society 44, 4 (1884-02-08), 208
322 # says that New York City Hall time was 3 minutes 58.4 seconds fast of
323 # Eastern time (i.e., -4:56:01.6) just before the 1883 switch. Round to the
326 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
327 Rule NYC 1920 only - Mar lastSun 2:00 1:00 D
328 Rule NYC 1920 only - Oct lastSun 2:00 0 S
329 Rule NYC 1921 1966 - Apr lastSun 2:00 1:00 D
330 Rule NYC 1921 1954 - Sep lastSun 2:00 0 S
331 Rule NYC 1955 1966 - Oct lastSun 2:00 0 S
332 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
333 Zone America/New_York -4:56:02 - LMT 1883 Nov 18 12:03:58
340 # US central time, represented by Chicago
342 # Alabama, Arkansas, Florida panhandle (Bay, Calhoun, Escambia,
343 # Gulf, Holmes, Jackson, Okaloosa, Santa Rosa, Walton, and
344 # Washington counties), Illinois, western Indiana
345 # (Gibson, Jasper, Lake, LaPorte, Newton, Porter, Posey, Spencer,
346 # Vanderburgh, and Warrick counties), Iowa, most of Kansas, western
347 # Kentucky, Louisiana, Minnesota, Mississippi, Missouri, eastern
348 # Nebraska, eastern North Dakota, Oklahoma, eastern South Dakota,
349 # western Tennessee, most of Texas, Wisconsin
351 # From Larry M. Smith (2006-04-26) re Wisconsin:
352 # https://docs.legis.wisconsin.gov/statutes/statutes/175.pdf
353 # is currently enforced at the 01:00 time of change. Because the local
354 # "bar time" in the state corresponds to 02:00, a number of citations
355 # are issued for the "sale of class 'B' alcohol after prohibited
356 # hours" within the deviated hour of this change every year....
358 # From Douglas R. Bomberg (2007-03-12):
359 # Wisconsin has enacted (nearly eleventh-hour) legislation to get WI
360 # Statue 175 closer in synch with the US Congress' intent....
361 # https://docs.legis.wisconsin.gov/2007/related/acts/3
363 # From an email administrator of the City of Fort Pierre, SD (2015-12-21):
364 # Fort Pierre is technically located in the Mountain time zone as is
365 # the rest of Stanley County. Most of Stanley County and Fort Pierre
366 # uses the Central time zone due to doing most of their business in
367 # Pierre so it simplifies schedules. I have lived in Stanley County
368 # all my life and it has been that way since I can remember. (43 years!)
370 # From Paul Eggert (2015-12-25):
371 # Assume this practice predates 1970, so Fort Pierre can use America/Chicago.
373 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
374 Rule Chicago 1920 only - Jun 13 2:00 1:00 D
375 Rule Chicago 1920 1921 - Oct lastSun 2:00 0 S
376 Rule Chicago 1921 only - Mar lastSun 2:00 1:00 D
377 Rule Chicago 1922 1966 - Apr lastSun 2:00 1:00 D
378 Rule Chicago 1922 1954 - Sep lastSun 2:00 0 S
379 Rule Chicago 1955 1966 - Oct lastSun 2:00 0 S
380 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
381 Zone America/Chicago -5:50:36 - LMT 1883 Nov 18 12:09:24
383 -6:00 Chicago C%sT 1936 Mar 1 2:00
384 -5:00 - EST 1936 Nov 15 2:00
385 -6:00 Chicago C%sT 1942
387 -6:00 Chicago C%sT 1967
389 # Oliver County, ND switched from mountain to central time on 1992-10-25.
390 Zone America/North_Dakota/Center -6:45:12 - LMT 1883 Nov 18 12:14:48
391 -7:00 US M%sT 1992 Oct 25 2:00
393 # Morton County, ND, switched from mountain to central time on
394 # 2003-10-26, except for the area around Mandan which was already central time.
395 # See <http://dmses.dot.gov/docimages/p63/135818.pdf>.
396 # Officially this switch also included part of Sioux County, and
397 # Jones, Mellette, and Todd Counties in South Dakota;
398 # but in practice these other counties were already observing central time.
399 # See <http://www.epa.gov/fedrgstr/EPA-IMPACT/2003/October/Day-28/i27056.htm>.
400 Zone America/North_Dakota/New_Salem -6:45:39 - LMT 1883 Nov 18 12:14:21
401 -7:00 US M%sT 2003 Oct 26 2:00
404 # From Josh Findley (2011-01-21):
405 # ...it appears that Mercer County, North Dakota, changed from the
406 # mountain time zone to the central time zone at the last transition from
407 # daylight-saving to standard time (on Nov. 7, 2010):
408 # https://www.gpo.gov/fdsys/pkg/FR-2010-09-29/html/2010-24376.htm
409 # http://www.bismarcktribune.com/news/local/article_1eb1b588-c758-11df-b472-001cc4c03286.html
411 # From Andy Lipscomb (2011-01-24):
412 # ...according to the Census Bureau, the largest city is Beulah (although
413 # it's commonly referred to as Beulah-Hazen, with Hazen being the next
414 # largest city in Mercer County). Google Maps places Beulah's city hall
415 # at 47 degrees 15' 51" N, 101 degrees 46' 40" W, which yields an offset
418 Zone America/North_Dakota/Beulah -6:47:07 - LMT 1883 Nov 18 12:12:53
419 -7:00 US M%sT 2010 Nov 7 2:00
422 # US mountain time, represented by Denver
424 # Colorado, far western Kansas, Montana, western
425 # Nebraska, Nevada border (Jackpot, Owyhee, and Mountain City),
426 # New Mexico, southwestern North Dakota,
427 # western South Dakota, far western Texas (El Paso County, Hudspeth County,
428 # and Pine Springs and Nickel Creek in Culberson County), Utah, Wyoming
430 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
431 Rule Denver 1920 1921 - Mar lastSun 2:00 1:00 D
432 Rule Denver 1920 only - Oct lastSun 2:00 0 S
433 Rule Denver 1921 only - May 22 2:00 0 S
434 Rule Denver 1965 1966 - Apr lastSun 2:00 1:00 D
435 Rule Denver 1965 1966 - Oct lastSun 2:00 0 S
436 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
437 Zone America/Denver -6:59:56 - LMT 1883 Nov 18 12:00:04
439 -7:00 Denver M%sT 1942
441 -7:00 Denver M%sT 1967
444 # US Pacific time, represented by Los Angeles
446 # California, northern Idaho (Benewah, Bonner, Boundary, Clearwater,
447 # Kootenai, Latah, Lewis, Nez Perce, and Shoshone counties, Idaho county
448 # north of the Salmon River, and the towns of Burgdorf and Warren),
449 # Nevada (except West Wendover), Oregon (except the northern 3/4 of
450 # Malheur county), and Washington
452 # From Paul Eggert (2016-08-20):
453 # In early February 1948, in response to California's electricity shortage,
454 # PG&E changed power frequency from 60 to 59.5 Hz during daylight hours,
455 # causing electric clocks to lose six minutes per day. (This did not change
456 # legal time, and is not part of the data here.) See:
457 # Ross SA. An energy crisis from the past: Northern California in 1948.
458 # Working Paper No. 8, Institute of Governmental Studies, UC Berkeley,
459 # 1973-11. https://escholarship.org/uc/item/8x22k30c
461 # In another measure to save electricity, DST was instituted from 1948-03-14
462 # at 02:01 to 1949-01-16 at 02:00, with the governor having the option to move
463 # the fallback transition earlier. See pages 3-4 of:
464 # http://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1948/48Vol1_Chapters.pdf
468 # Governor Warren received a torrent of objecting mail, and it is not too much
469 # to speculate that the objections to Daylight Saving Time were one important
470 # factor in the defeat of the Dewey-Warren Presidential ticket in California.
473 # On December 8 the governor exercised the option, setting the date to January 1
474 # (LA Times 1948-12-09). The transition time was 02:00 (LA Times 1949-01-01).
476 # Despite the controversy, in 1949 California voters approved Proposition 12,
477 # which established DST from April's last Sunday at 01:00 until September's
478 # last Sunday at 02:00. This was amended by 1962's Proposition 6, which changed
479 # the fall-back date to October's last Sunday. See:
480 # https://repository.uchastings.edu/cgi/viewcontent.cgi?article=1501&context=ca_ballot_props
481 # https://repository.uchastings.edu/cgi/viewcontent.cgi?article=1636&context=ca_ballot_props
483 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
484 Rule CA 1948 only - Mar 14 2:01 1:00 D
485 Rule CA 1949 only - Jan 1 2:00 0 S
486 Rule CA 1950 1966 - Apr lastSun 1:00 1:00 D
487 Rule CA 1950 1961 - Sep lastSun 2:00 0 S
488 Rule CA 1962 1966 - Oct lastSun 2:00 0 S
489 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
490 Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 12:07:02
496 # AK%sT is the modern abbreviation for -09 per USNO.
498 # From Paul Eggert (2017-06-15):
499 # Howse writes that Alaska switched from the Julian to the Gregorian calendar,
500 # and from east-of-GMT to west-of-GMT days, when the US bought it from Russia.
501 # On Friday, 1867-10-18 (Gregorian), at precisely 15:30 local time, the
502 # Russian forts and fleet at Sitka fired salutes to mark the ceremony of
503 # formal transfer. See the Sacramento Daily Union (1867-11-14), p 3, col 2.
504 # https://cdnc.ucr.edu/cgi-bin/cdnc?a=d&d=SDU18671114.2.12.1
505 # Sitka workers did not change their calendars until Sunday, 1867-10-20,
506 # and so celebrated two Sundays that week. See: Ahllund T (tr Hallamaa P).
507 # From the memoirs of a Finnish workman. Alaska History. 2006 Fall;21(2):1-25.
508 # http://alaskahistoricalsociety.org/wp-content/uploads/2016/12/Ahllund-2006-Memoirs-of-a-Finnish-Workman.pdf
509 # Include only the time zone part of this transition, ignoring the switch
510 # from Julian to Gregorian, since we can't represent the Julian calendar.
512 # As far as we know, of the locations mentioned below only Sitka was
513 # permanently inhabited in 1867 by anyone using either calendar.
514 # (Yakutat was colonized by the Russians in 1799, but the settlement was
515 # destroyed in 1805 by a Yakutat-kon war party.) Many of Alaska's inhabitants
516 # were unaware of the US acquisition of Alaska, much less of any calendar or
517 # time change. However, the Russian-influenced part of Alaska did observe
518 # Russian time, and it is more accurate to model this than to ignore it.
519 # The database format requires an exact transition time; use the Russian
520 # salute as a somewhat-arbitrary time for the formal transfer of control for
521 # all of Alaska. Sitka's UTC offset is -9:01:13; adjust its 15:30 to the
522 # local times of other Alaskan locations so that they change simultaneously.
524 # From Paul Eggert (2014-07-18):
525 # One opinion of the early-1980s turmoil in Alaska over time zones and
526 # daylight saving time appeared as graffiti on a Juneau airport wall:
527 # "Welcome to Juneau. Please turn your watch back to the 19th century."
528 # See: Turner W. Alaska's four time zones now two. NY Times 1983-11-01.
529 # http://www.nytimes.com/1983/11/01/us/alaska-s-four-time-zones-now-two.html
531 # Steve Ferguson (2011-01-31) referred to the following source:
532 # Norris F. Keeping time in Alaska: national directives, local response.
533 # Alaska History 2001;16(1-2).
534 # http://alaskahistoricalsociety.org/discover-alaska/glimpses-of-the-past/keeping-time-in-alaska/
536 # From Arthur David Olson (2011-02-01):
537 # Here's database-relevant material from the 2001 "Alaska History" article:
539 # On September 20 [1979]...DOT...officials decreed that on April 27,
540 # 1980, Juneau and other nearby communities would move to Yukon Time.
541 # Sitka, Petersburg, Wrangell, and Ketchikan, however, would remain on
544 # ...on September 22, 1980, DOT Secretary Neil E. Goldschmidt rescinded the
545 # Department's September 1979 decision. Juneau and other communities in
546 # northern Southeast reverted to Pacific Time on October 26.
548 # On October 28 [1983]...the Metlakatla Indian Community Council voted
549 # unanimously to keep the reservation on Pacific Time.
551 # According to DOT official Joanne Petrie, Indian reservations are not
552 # bound to follow time zones imposed by neighboring jurisdictions.
554 # (The last is consistent with how the database now handles the Navajo
557 # From Arthur David Olson (2011-02-09):
558 # I just spoke by phone with a staff member at the Metlakatla Indian
559 # Community office (using contact information available at
560 # http://www.commerce.state.ak.us/dca/commdb/CIS.cfm?Comm_Boro_name=Metlakatla
561 # It's shortly after 1:00 here on the east coast of the United States;
562 # the staffer said it was shortly after 10:00 there. When I asked whether
563 # that meant they were on Pacific time, they said no - they were on their
564 # own time. I asked about daylight saving; they said it wasn't used. I
565 # did not inquire about practices in the past.
567 # From Arthur David Olson (2011-08-17):
568 # For lack of better information, assume that Metlakatla's
569 # abandonment of use of daylight saving resulted from the 1983 vote.
571 # From Steffen Thorsen (2015-11-09):
572 # It seems Metlakatla did go off PST on Sunday, November 1, changing
573 # their time to AKST and are going to follow Alaska's DST, switching
574 # between AKST and AKDT from now on....
575 # https://www.krbd.org/2015/10/30/annette-island-times-they-are-a-changing/
577 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
578 Zone America/Juneau 15:02:19 - LMT 1867 Oct 19 15:33:32
579 -8:57:41 - LMT 1900 Aug 20 12:00
583 -8:00 US P%sT 1980 Apr 27 2:00
584 -9:00 US Y%sT 1980 Oct 26 2:00
585 -8:00 US P%sT 1983 Oct 30 2:00
586 -9:00 US Y%sT 1983 Nov 30
588 Zone America/Sitka 14:58:47 - LMT 1867 Oct 19 15:30
589 -9:01:13 - LMT 1900 Aug 20 12:00
593 -8:00 US P%sT 1983 Oct 30 2:00
594 -9:00 US Y%sT 1983 Nov 30
596 Zone America/Metlakatla 15:13:42 - LMT 1867 Oct 19 15:44:55
597 -8:46:18 - LMT 1900 Aug 20 12:00
601 -8:00 US P%sT 1983 Oct 30 2:00
602 -8:00 - PST 2015 Nov 1 2:00
604 Zone America/Yakutat 14:41:05 - LMT 1867 Oct 19 15:12:18
605 -9:18:55 - LMT 1900 Aug 20 12:00
609 -9:00 US Y%sT 1983 Nov 30
611 Zone America/Anchorage 14:00:24 - LMT 1867 Oct 19 14:31:37
612 -9:59:36 - LMT 1900 Aug 20 12:00
614 -10:00 US A%sT 1967 Apr
616 -10:00 US AH%sT 1983 Oct 30 2:00
617 -9:00 US Y%sT 1983 Nov 30
619 Zone America/Nome 12:58:22 - LMT 1867 Oct 19 13:29:35
620 -11:01:38 - LMT 1900 Aug 20 12:00
623 -11:00 - NST 1967 Apr
625 -11:00 US B%sT 1983 Oct 30 2:00
626 -9:00 US Y%sT 1983 Nov 30
628 Zone America/Adak 12:13:22 - LMT 1867 Oct 19 12:44:35
629 -11:46:38 - LMT 1900 Aug 20 12:00
632 -11:00 - NST 1967 Apr
634 -11:00 US B%sT 1983 Oct 30 2:00
635 -10:00 US AH%sT 1983 Nov 30
637 # The following switches don't quite make our 1970 cutoff.
639 # Shanks writes that part of southwest Alaska (e.g. Aniak)
640 # switched from -11:00 to -10:00 on 1968-09-22 at 02:00,
641 # and another part (e.g. Akiak) made the same switch five weeks later.
643 # From David Flater (2004-11-09):
644 # In e-mail, 2004-11-02, Ray Hudson, historian/liaison to the Unalaska
645 # Historic Preservation Commission, provided this information, which
646 # suggests that Unalaska deviated from statutory time from early 1967
647 # possibly until 1983:
649 # Minutes of the Unalaska City Council Meeting, January 10, 1967:
650 # "Except for St. Paul and Akutan, Unalaska is the only important
651 # location not on Alaska Standard Time. The following resolution was
652 # made by William Robinson and seconded by Henry Swanson: Be it
653 # resolved that the City of Unalaska hereby goes to Alaska Standard
654 # Time as of midnight Friday, January 13, 1967 (1 A.M. Saturday,
655 # January 14, Alaska Standard Time.) This resolution was passed with
656 # three votes for and one against."
660 # From Arthur David Olson (2010-12-09):
661 # "Hawaiian Time" by Robert C. Schmitt and Doak C. Cox appears on pages 207-225
662 # of volume 26 of The Hawaiian Journal of History (1992). As of 2010-12-09,
663 # the article is available at
664 # https://evols.library.manoa.hawaii.edu/bitstream/10524/239/2/JL26215.pdf
665 # and indicates that standard time was adopted effective noon, January
666 # 13, 1896 (page 218), that in "1933, the Legislature decreed daylight
667 # saving for the period between the last Sunday of each April and the
668 # last Sunday of each September, but less than a month later repealed the
669 # act," (page 220), that year-round daylight saving time was in effect
670 # from 1942-02-09 to 1945-09-30 (page 221, with no time of day given for
671 # when clocks changed) and that clocks were changed by 30 minutes
672 # effective the second Sunday of June, 1947 (page 219, with no time of
673 # day given for when clocks changed). A footnote for the 1933 changes
674 # cites Session Laws of Hawaii 1933, "Act. 90 (approved 26 Apr. 1933)
675 # and Act 163 (approved 21 May 1933)."
677 # From Arthur David Olson (2011-01-19):
678 # The following is from "Laws of the Territory of Hawaii Passed by the
679 # Seventeenth Legislature: Regular Session 1933," available (as of
680 # 2011-01-19) at American University's Pence Law Library. Page 85: "Act
681 # 90...At 2 o'clock ante meridian of the last Sunday in April of each
682 # year, the standard time of this Territory shall be advanced one
683 # hour...This Act shall take effect upon its approval. Approved this 26th
684 # day of April, A. D. 1933. LAWRENCE M JUDD, Governor of the Territory of
685 # Hawaii." Page 172: "Act 163...Act 90 of the Session Laws of 1933 is
686 # hereby repealed...This Act shall take effect upon its approval, upon
687 # which date the standard time of this Territory shall be restored to
688 # that existing immediately prior to the taking effect of said Act 90.
689 # Approved this 21st day of May, A. D. 1933. LAWRENCE M. JUDD, Governor
690 # of the Territory of Hawaii."
692 # Note that 1933-05-21 was a Sunday.
693 # We're left to guess the time of day when Act 163 was approved; guess noon.
695 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
696 Zone Pacific/Honolulu -10:31:26 - LMT 1896 Jan 13 12:00
697 -10:30 - HST 1933 Apr 30 2:00
698 -10:30 1:00 HDT 1933 May 21 12:00
699 -10:30 - HST 1942 Feb 9 2:00
700 -10:30 1:00 HDT 1945 Sep 30 2:00
701 -10:30 - HST 1947 Jun 8 2:00
704 # Now we turn to US areas that have diverged from the consensus since 1970.
706 # Arizona mostly uses MST.
708 # From Paul Eggert (2002-10-20):
710 # The information in the rest of this paragraph is derived from the
711 # Daylight Saving Time web page
712 # <http://www.dlapr.lib.az.us/links/daylight.htm> (2002-01-23)
713 # maintained by the Arizona State Library, Archives and Public Records.
714 # Between 1944-01-01 and 1944-04-01 the State of Arizona used standard
715 # time, but by federal law railroads, airlines, bus lines, military
716 # personnel, and some engaged in interstate commerce continued to
717 # observe war (i.e., daylight saving) time. The 1944-03-17 Phoenix
718 # Gazette says that was the date the law changed, and that 04-01 was
719 # the date the state's clocks would change. In 1945 the State of
720 # Arizona used standard time all year, again with exceptions only as
721 # mandated by federal law. Arizona observed DST in 1967, but Arizona
722 # Laws 1968, ch. 183 (effective 1968-03-21) repealed DST.
724 # Shanks says the 1944 experiment came to an end on 1944-03-17.
725 # Go with the Arizona State Library instead.
727 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
728 Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 11:31:42
729 -7:00 US M%sT 1944 Jan 1 0:01
730 -7:00 - MST 1944 Apr 1 0:01
731 -7:00 US M%sT 1944 Oct 1 0:01
733 -7:00 US M%sT 1968 Mar 21
735 # From Arthur David Olson (1988-02-13):
736 # A writer from the Inter Tribal Council of Arizona, Inc.,
737 # notes in private correspondence dated 1987-12-28 that "Presently, only the
738 # Navajo Nation participates in the Daylight Saving Time policy, due to its
739 # large size and location in three states." (The "only" means that other
740 # tribal nations don't use DST.)
742 # From Paul Eggert (2013-08-26):
743 # See America/Denver for a zone appropriate for the Navajo Nation.
745 # Southern Idaho (Ada, Adams, Bannock, Bear Lake, Bingham, Blaine,
746 # Boise, Bonneville, Butte, Camas, Canyon, Caribou, Cassia, Clark,
747 # Custer, Elmore, Franklin, Fremont, Gem, Gooding, Jefferson, Jerome,
748 # Lemhi, Lincoln, Madison, Minidoka, Oneida, Owyhee, Payette, Power,
749 # Teton, Twin Falls, Valley, Washington counties, and the southern
750 # quarter of Idaho county) and eastern Oregon (most of Malheur County)
751 # switched four weeks late in 1974.
753 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
754 Zone America/Boise -7:44:49 - LMT 1883 Nov 18 12:15:11
755 -8:00 US P%sT 1923 May 13 2:00
757 -7:00 - MST 1974 Feb 3 2:00
762 # For a map of Indiana's time zone regions, see:
763 # https://en.wikipedia.org/wiki/Time_in_Indiana
765 # From Paul Eggert (2007-08-17):
766 # Since 1970, most of Indiana has been like America/Indiana/Indianapolis,
767 # with the following exceptions:
769 # - Gibson, Jasper, Lake, LaPorte, Newton, Porter, Posey, Spencer,
770 # Vanderburgh, and Warrick counties have been like America/Chicago.
772 # - Dearborn and Ohio counties have been like America/New_York.
774 # - Clark, Floyd, and Harrison counties have been like
775 # America/Kentucky/Louisville.
777 # - Crawford, Daviess, Dubois, Knox, Martin, Perry, Pike, Pulaski, Starke,
778 # and Switzerland counties have their own time zone histories as noted below.
780 # Shanks partitioned Indiana into 345 regions, each with its own time history,
781 # and wrote "Even newspaper reports present contradictory information."
782 # Those Hoosiers! Such a flighty and changeable people!
783 # Fortunately, most of the complexity occurred before our cutoff date of 1970.
785 # Other than Indianapolis, the Indiana place names are so nondescript
786 # that they would be ambiguous if we left them at the 'America' level.
787 # So we reluctantly put them all in a subdirectory 'America/Indiana'.
789 # From Paul Eggert (2014-06-26):
790 # https://www.federalregister.gov/articles/2006/01/20/06-563/standard-time-zone-boundary-in-the-state-of-indiana
791 # says "DOT is relocating the time zone boundary in Indiana to move Starke,
792 # Pulaski, Knox, Daviess, Martin, Pike, Dubois, and Perry Counties from the
793 # Eastern Time Zone to the Central Time Zone.... The effective date of
794 # this rule is 2 a.m. EST Sunday, April 2, 2006, which is the
795 # changeover date from standard time to Daylight Saving Time."
796 # Strictly speaking, this meant the affected counties changed their
797 # clocks twice that night, but this obviously was in error. The intent
798 # was that 01:59:59 EST be followed by 02:00:00 CDT.
800 # From Gwillim Law (2007-02-10):
801 # The Associated Press has been reporting that Pulaski County, Indiana is
802 # going to switch from Central to Eastern Time on March 11, 2007....
803 # http://www.indystar.com/apps/pbcs.dll/article?AID=/20070207/LOCAL190108/702070524/0/LOCAL
805 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
806 Rule Indianapolis 1941 only - Jun 22 2:00 1:00 D
807 Rule Indianapolis 1941 1954 - Sep lastSun 2:00 0 S
808 Rule Indianapolis 1946 1954 - Apr lastSun 2:00 1:00 D
809 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
810 Zone America/Indiana/Indianapolis -5:44:38 - LMT 1883 Nov 18 12:15:22
812 -6:00 Indianapolis C%sT 1942
814 -6:00 Indianapolis C%sT 1955 Apr 24 2:00
815 -5:00 - EST 1957 Sep 29 2:00
816 -6:00 - CST 1958 Apr 27 2:00
822 # Eastern Crawford County, Indiana, left its clocks alone in 1974,
823 # as well as from 1976 through 2005.
824 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
825 Rule Marengo 1951 only - Apr lastSun 2:00 1:00 D
826 Rule Marengo 1951 only - Sep lastSun 2:00 0 S
827 Rule Marengo 1954 1960 - Apr lastSun 2:00 1:00 D
828 Rule Marengo 1954 1960 - Sep lastSun 2:00 0 S
829 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
830 Zone America/Indiana/Marengo -5:45:23 - LMT 1883 Nov 18 12:14:37
832 -6:00 Marengo C%sT 1961 Apr 30 2:00
834 -5:00 US E%sT 1974 Jan 6 2:00
835 -6:00 1:00 CDT 1974 Oct 27 2:00
840 # Daviess, Dubois, Knox, and Martin Counties, Indiana,
841 # switched from eastern to central time in April 2006, then switched back
843 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
844 Rule Vincennes 1946 only - Apr lastSun 2:00 1:00 D
845 Rule Vincennes 1946 only - Sep lastSun 2:00 0 S
846 Rule Vincennes 1953 1954 - Apr lastSun 2:00 1:00 D
847 Rule Vincennes 1953 1959 - Sep lastSun 2:00 0 S
848 Rule Vincennes 1955 only - May 1 0:00 1:00 D
849 Rule Vincennes 1956 1963 - Apr lastSun 2:00 1:00 D
850 Rule Vincennes 1960 only - Oct lastSun 2:00 0 S
851 Rule Vincennes 1961 only - Sep lastSun 2:00 0 S
852 Rule Vincennes 1962 1963 - Oct lastSun 2:00 0 S
853 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
854 Zone America/Indiana/Vincennes -5:50:07 - LMT 1883 Nov 18 12:09:53
856 -6:00 Vincennes C%sT 1964 Apr 26 2:00
859 -5:00 - EST 2006 Apr 2 2:00
860 -6:00 US C%sT 2007 Nov 4 2:00
863 # Perry County, Indiana, switched from eastern to central time in April 2006.
864 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
865 Rule Perry 1946 only - Apr lastSun 2:00 1:00 D
866 Rule Perry 1946 only - Sep lastSun 2:00 0 S
867 Rule Perry 1953 1954 - Apr lastSun 2:00 1:00 D
868 Rule Perry 1953 1959 - Sep lastSun 2:00 0 S
869 Rule Perry 1955 only - May 1 0:00 1:00 D
870 Rule Perry 1956 1963 - Apr lastSun 2:00 1:00 D
871 Rule Perry 1960 only - Oct lastSun 2:00 0 S
872 Rule Perry 1961 only - Sep lastSun 2:00 0 S
873 Rule Perry 1962 1963 - Oct lastSun 2:00 0 S
874 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
875 Zone America/Indiana/Tell_City -5:47:03 - LMT 1883 Nov 18 12:12:57
877 -6:00 Perry C%sT 1964 Apr 26 2:00
880 -5:00 - EST 2006 Apr 2 2:00
883 # Pike County, Indiana moved from central to eastern time in 1977,
884 # then switched back in 2006, then switched back again in 2007.
885 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
886 Rule Pike 1955 only - May 1 0:00 1:00 D
887 Rule Pike 1955 1960 - Sep lastSun 2:00 0 S
888 Rule Pike 1956 1964 - Apr lastSun 2:00 1:00 D
889 Rule Pike 1961 1964 - Oct lastSun 2:00 0 S
890 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
891 Zone America/Indiana/Petersburg -5:49:07 - LMT 1883 Nov 18 12:10:53
893 -6:00 Pike C%sT 1965 Apr 25 2:00
894 -5:00 - EST 1966 Oct 30 2:00
895 -6:00 US C%sT 1977 Oct 30 2:00
896 -5:00 - EST 2006 Apr 2 2:00
897 -6:00 US C%sT 2007 Nov 4 2:00
900 # Starke County, Indiana moved from central to eastern time in 1991,
901 # then switched back in 2006.
902 # From Arthur David Olson (1991-10-28):
903 # An article on page A3 of the Sunday, 1991-10-27 Washington Post
904 # notes that Starke County switched from Central time to Eastern time as of
906 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
907 Rule Starke 1947 1961 - Apr lastSun 2:00 1:00 D
908 Rule Starke 1947 1954 - Sep lastSun 2:00 0 S
909 Rule Starke 1955 1956 - Oct lastSun 2:00 0 S
910 Rule Starke 1957 1958 - Sep lastSun 2:00 0 S
911 Rule Starke 1959 1961 - Oct lastSun 2:00 0 S
912 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
913 Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 12:13:30
915 -6:00 Starke C%sT 1962 Apr 29 2:00
916 -5:00 - EST 1963 Oct 27 2:00
917 -6:00 US C%sT 1991 Oct 27 2:00
918 -5:00 - EST 2006 Apr 2 2:00
921 # Pulaski County, Indiana, switched from eastern to central time in
922 # April 2006 and then switched back in March 2007.
923 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
924 Rule Pulaski 1946 1960 - Apr lastSun 2:00 1:00 D
925 Rule Pulaski 1946 1954 - Sep lastSun 2:00 0 S
926 Rule Pulaski 1955 1956 - Oct lastSun 2:00 0 S
927 Rule Pulaski 1957 1960 - Sep lastSun 2:00 0 S
928 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
929 Zone America/Indiana/Winamac -5:46:25 - LMT 1883 Nov 18 12:13:35
931 -6:00 Pulaski C%sT 1961 Apr 30 2:00
934 -5:00 - EST 2006 Apr 2 2:00
935 -6:00 US C%sT 2007 Mar 11 2:00
938 # Switzerland County, Indiana, did not observe DST from 1973 through 2005.
939 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
940 Zone America/Indiana/Vevay -5:40:16 - LMT 1883 Nov 18 12:19:44
941 -6:00 US C%sT 1954 Apr 25 2:00
947 # Part of Kentucky left its clocks alone in 1974.
948 # This also includes Clark, Floyd, and Harrison counties in Indiana.
949 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
950 Rule Louisville 1921 only - May 1 2:00 1:00 D
951 Rule Louisville 1921 only - Sep 1 2:00 0 S
952 Rule Louisville 1941 1961 - Apr lastSun 2:00 1:00 D
953 Rule Louisville 1941 only - Sep lastSun 2:00 0 S
954 Rule Louisville 1946 only - Jun 2 2:00 0 S
955 Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S
956 Rule Louisville 1956 1960 - Oct lastSun 2:00 0 S
957 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
958 Zone America/Kentucky/Louisville -5:43:02 - LMT 1883 Nov 18 12:16:58
960 -6:00 Louisville C%sT 1942
962 -6:00 Louisville C%sT 1961 Jul 23 2:00
964 -5:00 US E%sT 1974 Jan 6 2:00
965 -6:00 1:00 CDT 1974 Oct 27 2:00
968 # Wayne County, Kentucky
970 # From Lake Cumberland LIFE
971 # http://www.lake-cumberland.com/life/archive/news990129time.shtml
972 # (1999-01-29) via WKYM-101.7:
973 # Clinton County has joined Wayne County in asking the DoT to change from
974 # the Central to the Eastern time zone.... The Wayne County government made
975 # the same request in December. And while Russell County officials have not
976 # taken action, the majority of respondents to a poll conducted there in
977 # August indicated they would like to change to "fast time" also.
978 # The three Lake Cumberland counties are the farthest east of any U.S.
979 # location in the Central time zone.
981 # From Rich Wales (2000-08-29):
982 # After prolonged debate, and despite continuing deep differences of opinion,
983 # Wayne County (central Kentucky) is switching from Central (-0600) to Eastern
984 # (-0500) time. They won't "fall back" this year. See Sara Shipley,
985 # The difference an hour makes, Nando Times (2000-08-29 15:33 -0400).
987 # From Paul Eggert (2001-07-16):
988 # The final rule was published in the
989 # Federal Register 65, 160 (2000-08-17), pp 50154-50158.
990 # https://www.gpo.gov/fdsys/pkg/FR-2000-08-17/html/00-20854.htm
992 Zone America/Kentucky/Monticello -5:39:24 - LMT 1883 Nov 18 12:20:36
995 -6:00 US C%sT 2000 Oct 29 2:00
999 # From Rives McDow (2000-08-30):
1000 # Here ... are all the changes in the US since 1985.
1001 # Kearny County, KS (put all of county on central;
1002 # previously split between MST and CST) ... 1990-10
1003 # Starke County, IN (from CST to EST) ... 1991-10
1004 # Oliver County, ND (from MST to CST) ... 1992-10
1005 # West Wendover, NV (from PST TO MST) ... 1999-10
1006 # Wayne County, KY (from CST to EST) ... 2000-10
1008 # From Paul Eggert (2001-07-17):
1009 # We don't know where the line used to be within Kearny County, KS,
1010 # so omit that change for now.
1011 # See America/Indiana/Knox for the Starke County, IN change.
1012 # See America/North_Dakota/Center for the Oliver County, ND change.
1013 # West Wendover, NV officially switched from Pacific to mountain time on
1014 # 1999-10-31. See the
1015 # Federal Register 64, 203 (1999-10-21), pp 56705-56707.
1016 # https://www.gpo.gov/fdsys/pkg/FR-1999-10-21/html/99-27240.htm
1017 # However, the Federal Register says that West Wendover already operated
1018 # on mountain time, and the rule merely made this official;
1019 # hence a separate tz entry is not needed.
1023 # From Bob Devine (1988-01-28):
1024 # Michigan didn't observe DST from 1968 to 1973.
1026 # From Paul Eggert (1999-03-31):
1027 # Shanks writes that Michigan started using standard time on 1885-09-18,
1028 # but Howse writes (pp 124-125, referring to Popular Astronomy, 1901-01)
1031 # local time until 1900 when the City Council decreed that clocks should
1032 # be put back twenty-eight minutes to Central Standard Time. Half the
1033 # city obeyed, half refused. After considerable debate, the decision
1034 # was rescinded and the city reverted to Sun time. A derisive offer to
1035 # erect a sundial in front of the city hall was referred to the
1036 # Committee on Sewers. Then, in 1905, Central time was adopted
1039 # This story is too entertaining to be false, so go with Howse over Shanks.
1041 # From Paul Eggert (2001-03-06):
1042 # Garland (1927) writes "Cleveland and Detroit advanced their clocks
1043 # one hour in 1914." This change is not in Shanks. We have no more
1044 # info, so omit this for now.
1046 # From Paul Eggert (2017-07-26):
1047 # Although Shanks says Detroit observed DST in 1967 from 06-14 00:01
1048 # until 10-29 00:01, I now see multiple reports that this is incorrect.
1049 # For example, according to a 50-year anniversary report about the 1967
1050 # Detroit riots and a major-league doubleheader on 1967-07-23, "By the time
1051 # the last fly ball of the doubleheader settled into the glove of leftfielder
1052 # Lenny Green, it was after 7 p.m. Detroit did not observe daylight saving
1053 # time, so light was already starting to fail. Twilight was made even deeper
1054 # by billowing columns of smoke that ascended in an unbroken wall north of the
1055 # ballpark." See: Dow B. Detroit '67: As violence unfolded, Tigers played two
1056 # at home vs. Yankees. Detroit Free Press 2017-07-23.
1057 # https://www.freep.com/story/sports/mlb/tigers/2017/07/23/detroit-tigers-1967-riot-new-york-yankees/499951001/
1059 # Most of Michigan observed DST from 1973 on, but was a bit late in 1975.
1060 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
1061 Rule Detroit 1948 only - Apr lastSun 2:00 1:00 D
1062 Rule Detroit 1948 only - Sep lastSun 2:00 0 S
1063 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1064 Zone America/Detroit -5:32:11 - LMT 1905
1065 -6:00 - CST 1915 May 15 2:00
1068 -5:00 Detroit E%sT 1973
1070 -5:00 - EST 1975 Apr 27 2:00
1073 # Dickinson, Gogebic, Iron, and Menominee Counties, Michigan,
1074 # switched from EST to CST/CDT in 1973.
1075 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
1076 Rule Menominee 1946 only - Apr lastSun 2:00 1:00 D
1077 Rule Menominee 1946 only - Sep lastSun 2:00 0 S
1078 Rule Menominee 1966 only - Apr lastSun 2:00 1:00 D
1079 Rule Menominee 1966 only - Oct lastSun 2:00 0 S
1080 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1081 Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00
1083 -6:00 Menominee C%sT 1969 Apr 27 2:00
1084 -5:00 - EST 1973 Apr 29 2:00
1088 # administered by the US Fish and Wildlife Service
1089 # claimed by US under the provisions of the 1856 Guano Islands Act
1090 # also claimed by Haiti
1091 # occupied 1857/1900 by the Navassa Phosphate Co
1092 # US lighthouse 1917/1996-09
1093 # currently uninhabited
1094 # see Mark Fineman, "An Isle Rich in Guano and Discord",
1095 # _Los Angeles Times_ (1998-11-10), A1, A10; it cites
1096 # Jimmy Skaggs, _The Great Guano Rush_ (1994).
1098 ################################################################################
1101 # From Paul Eggert (2017-02-10):
1103 # Unless otherwise specified, the source for data through 1990 is:
1104 # Thomas G. Shanks and Rique Pottenger, The International Atlas (6th edition),
1105 # San Diego: ACS Publications, Inc. (2003).
1106 # Unfortunately this book contains many errors and cites no sources.
1108 # Many years ago Gwillim Law wrote that a good source
1109 # for time zone data was the International Air Transport
1110 # Association's Standard Schedules Information Manual (IATA SSIM),
1111 # published semiannually. Law sent in several helpful summaries
1112 # of the IATA's data after 1990. Except where otherwise noted,
1113 # IATA SSIM is the source for entries after 1990.
1115 # Other sources occasionally used include:
1117 # Edward W. Whitman, World Time Differences,
1118 # Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated),
1119 # which I found in the UCLA library.
1121 # William Willett, The Waste of Daylight, 19th edition
1122 # <http://cs.ucla.edu/~eggert/The-Waste-of-Daylight-19th.pdf>
1125 # Milne J. Civil time. Geogr J. 1899 Feb;13(2):173-94
1126 # <https://www.jstor.org/stable/1774359>.
1128 # See the 'europe' file for Greenland.
1132 # From Alain LaBonté (1994-11-14):
1133 # I post here the time zone abbreviations standardized in Canada
1134 # for both English and French in the CAN/CSA-Z234.4-89 standard....
1136 # UTC Standard time Daylight saving time
1137 # offset French English French English
1141 # -4 HNA AST HAE EDT
1142 # -5 HNE EST HAC CDT
1143 # -6 HNC CST HAR MDT
1144 # -7 HNR MST HAP PDT
1145 # -8 HNP PST HAY YDT
1148 # HN: Heure Normale ST: Standard Time
1149 # HA: Heure Avancée DT: Daylight saving Time
1151 # A: de l'Atlantique Atlantic
1152 # C: du Centre Central
1153 # E: de l'Est Eastern
1156 # P: du Pacifique Pacific
1161 # From Paul Eggert (1994-11-22):
1162 # Alas, this sort of thing must be handled by localization software.
1164 # Unless otherwise specified, the data entries for Canada are all from Shanks
1167 # From Chris Walton (2006-04-01, 2006-04-25, 2006-06-26, 2007-01-31,
1169 # The British Columbia government announced yesterday that it will
1170 # adjust daylight savings next year to align with changes in the
1171 # U.S. and the rest of Canada....
1172 # https://archive.news.gov.bc.ca/releases/news_releases_2005-2009/2006AG0014-000330.htm
1175 # Daylight saving time will be extended by four weeks starting in 2007....
1176 # https://www.novascotia.ca/just/regulations/rg2/2006/ma1206.pdf
1178 # [For New Brunswick] the new legislation dictates that the time change is to
1179 # be done at 02:00 instead of 00:01.
1180 # https://www.gnb.ca/0062/acts/BBA-2006/Chap-19.pdf
1182 # Manitoba has traditionally changed the clock every fall at 03:00.
1183 # As of 2006, the transition is to take place one hour earlier at 02:00.
1184 # https://web2.gov.mb.ca/laws/statutes/ccsm/o030e.php
1186 # [Alberta, Ontario, Quebec] will follow US rules.
1187 # http://www.qp.gov.ab.ca/documents/spring/CH03_06.CFM
1188 # http://www.e-laws.gov.on.ca/DBLaws/Source/Regs/English/2006/R06111_e.htm
1189 # http://www2.publicationsduquebec.gouv.qc.ca/dynamicSearch/telecharge.php?type=5&file=2006C39A.PDF
1191 # P.E.I. will follow US rules....
1192 # http://www.assembly.pe.ca/bills/pdf_chapter/62/3/chapter-41.pdf
1194 # Province of Newfoundland and Labrador....
1195 # http://www.hoa.gov.nl.ca/hoa/bills/Bill0634.htm
1198 # https://www.gov.yk.ca/legislation/regs/oic2006_127.pdf
1200 # N.W.T. will follow US rules. Whoever maintains the government web site
1201 # does not seem to believe in bookmarks. To see the news release, click the
1202 # following link and search for "Daylight Savings Time Change". Press the
1203 # "Daylight Savings Time Change" link; it will fire off a popup using
1205 # http://www.exec.gov.nt.ca/currentnews/currentPR.asp?mode=archive
1208 # An amendment to the Interpretation Act was registered on February 19/2007....
1209 # http://action.attavik.ca/home/justice-gn/attach/2007/gaz02part2.pdf
1211 # From Paul Eggert (2014-10-18):
1212 # H. David Matthews and Mary Vincent's map
1213 # "It's about TIME", _Canadian Geographic_ (September-October 1998)
1214 # http://www.canadiangeographic.ca/Magazine/SO98/alacarte.asp
1215 # contains detailed boundaries for regions observing nonstandard
1216 # time and daylight saving time arrangements in Canada circa 1998.
1218 # National Research Council Canada maintains info about time zones and DST.
1219 # https://www.nrc-cnrc.gc.ca/eng/services/time/time_zones.html
1220 # https://www.nrc-cnrc.gc.ca/eng/services/time/faq/index.html#Q5
1221 # Its unofficial information is often taken from Matthews and Vincent.
1223 # From Paul Eggert (2006-06-27):
1224 # For now, assume all of DST-observing Canada will fall into line with the
1227 # From Chris Walton (2011-12-01)
1228 # In the first of Tammy Hardwick's articles
1229 # http://www.ilovecreston.com/?p=articles&t=spec&ar=260
1230 # she quotes the Friday November 1/1918 edition of the Creston Review.
1231 # The quote includes these two statements:
1232 # 'Sunday the CPR went back to the old system of time...'
1233 # '... The daylight saving scheme was dropped all over Canada at the same time,'
1234 # These statements refer to a transition from daylight time to standard time
1235 # that occurred nationally on Sunday October 27/1918. This transition was
1236 # also documented in the Saturday October 26/1918 edition of the Toronto Star.
1238 # In light of that evidence, we alter the date from the earlier believed
1239 # Oct 31, to Oct 27, 1918 (and Sunday is a more likely transition day
1240 # than Thursday) in all Canadian rulesets.
1242 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1243 Rule Canada 1918 only - Apr 14 2:00 1:00 D
1244 Rule Canada 1918 only - Oct 27 2:00 0 S
1245 Rule Canada 1942 only - Feb 9 2:00 1:00 W # War
1246 Rule Canada 1945 only - Aug 14 23:00u 1:00 P # Peace
1247 Rule Canada 1945 only - Sep 30 2:00 0 S
1248 Rule Canada 1974 1986 - Apr lastSun 2:00 1:00 D
1249 Rule Canada 1974 2006 - Oct lastSun 2:00 0 S
1250 Rule Canada 1987 2006 - Apr Sun>=1 2:00 1:00 D
1251 Rule Canada 2007 max - Mar Sun>=8 2:00 1:00 D
1252 Rule Canada 2007 max - Nov Sun>=1 2:00 0 S
1255 # Newfoundland and Labrador
1257 # From Paul Eggert (2017-10-14):
1258 # Legally Labrador should observe Newfoundland time; see:
1259 # McLeod J. Labrador time - legal or not? St. John's Telegram, 2017-10-07
1260 # http://www.thetelegram.com/news/local/labrador-time--legal-or-not-154860/
1261 # Matthews and Vincent (1998) write that the only part of Labrador
1262 # that follows the rules is the southeast corner, including Port Hope
1263 # Simpson and Mary's Harbour, but excluding, say, Black Tickle.
1265 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1266 Rule StJohns 1917 only - Apr 8 2:00 1:00 D
1267 Rule StJohns 1917 only - Sep 17 2:00 0 S
1268 # Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks & Pottenger.
1269 Rule StJohns 1919 only - May 5 23:00 1:00 D
1270 Rule StJohns 1919 only - Aug 12 23:00 0 S
1271 # For 1931-1935 Whitman gives Apr same date; go with Shanks & Pottenger.
1272 Rule StJohns 1920 1935 - May Sun>=1 23:00 1:00 D
1273 Rule StJohns 1920 1935 - Oct lastSun 23:00 0 S
1274 # For 1936-1941 Whitman gives May Sun>=8 and Oct Sun>=1; go with Shanks &
1276 Rule StJohns 1936 1941 - May Mon>=9 0:00 1:00 D
1277 Rule StJohns 1936 1941 - Oct Mon>=2 0:00 0 S
1278 # Whitman gives the following transitions:
1279 # 1942 03-01/12-31, 1943 05-30/09-05, 1944 07-10/09-02, 1945 01-01/10-07
1280 # but go with Shanks & Pottenger and assume they used Canadian rules.
1281 # For 1946-9 Whitman gives May 5,4,9,1 - Oct 1,5,3,2, and for 1950 he gives
1282 # Apr 30 - Sep 24; go with Shanks & Pottenger.
1283 Rule StJohns 1946 1950 - May Sun>=8 2:00 1:00 D
1284 Rule StJohns 1946 1950 - Oct Sun>=2 2:00 0 S
1285 Rule StJohns 1951 1986 - Apr lastSun 2:00 1:00 D
1286 Rule StJohns 1951 1959 - Sep lastSun 2:00 0 S
1287 Rule StJohns 1960 1986 - Oct lastSun 2:00 0 S
1288 # From Paul Eggert (2000-10-02):
1289 # INMS (2000-09-12) says that, since 1988 at least, Newfoundland switches
1290 # at 00:01 local time. For now, assume it started in 1987.
1292 # From Michael Pelley (2011-09-12):
1293 # We received today, Monday, September 12, 2011, notification that the
1294 # changes to the Newfoundland Standard Time Act have been proclaimed.
1295 # The change in the Act stipulates that the change from Daylight Savings
1296 # Time to Standard Time and from Standard Time to Daylight Savings Time
1297 # now occurs at 2:00AM.
1299 # http://www.assembly.nl.ca/legislation/sr/annualstatutes/2011/1106.chp.htm
1301 # MICHAEL PELLEY | Manager of Enterprise Architecture - Solution Delivery
1302 # Office of the Chief Information Officer
1304 # Government of Newfoundland & Labrador
1306 Rule StJohns 1987 only - Apr Sun>=1 0:01 1:00 D
1307 Rule StJohns 1987 2006 - Oct lastSun 0:01 0 S
1308 Rule StJohns 1988 only - Apr Sun>=1 0:01 2:00 DD
1309 Rule StJohns 1989 2006 - Apr Sun>=1 0:01 1:00 D
1310 Rule StJohns 2007 2011 - Mar Sun>=8 0:01 1:00 D
1311 Rule StJohns 2007 2010 - Nov Sun>=1 0:01 0 S
1313 # St John's has an apostrophe, but Posix file names can't have apostrophes.
1314 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1315 Zone America/St_Johns -3:30:52 - LMT 1884
1316 -3:30:52 StJohns N%sT 1918
1317 -3:30:52 Canada N%sT 1919
1318 -3:30:52 StJohns N%sT 1935 Mar 30
1319 -3:30 StJohns N%sT 1942 May 11
1320 -3:30 Canada N%sT 1946
1321 -3:30 StJohns N%sT 2011 Nov
1324 # most of east Labrador
1326 # The name 'Happy Valley-Goose Bay' is too long; use 'Goose Bay'.
1327 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1328 Zone America/Goose_Bay -4:01:40 - LMT 1884 # Happy Valley-Goose Bay
1330 -3:30:52 Canada N%sT 1919
1331 -3:30:52 - NST 1935 Mar 30
1333 -3:30 StJohns N%sT 1942 May 11
1334 -3:30 Canada N%sT 1946
1335 -3:30 StJohns N%sT 1966 Mar 15 2:00
1336 -4:00 StJohns A%sT 2011 Nov
1340 # west Labrador, Nova Scotia, Prince Edward I
1342 # From Brian Inglis (2015-07-20):
1343 # From the historical weather station records available at:
1344 # https://weatherspark.com/history/28351/1971/Sydney-Nova-Scotia-Canada
1345 # Sydney shares the same time history as Glace Bay, so was
1346 # likely to be the same across the island....
1347 # Sydney, as the capital and most populous location, or Cape Breton, would
1348 # have been better names for the zone had we known this in 1996.
1350 # From Paul Eggert (2015-07-20):
1351 # Shanks & Pottenger write that since 1970 most of this region has been like
1352 # Halifax. Many locales did not observe peacetime DST until 1972;
1353 # the Cape Breton area, represented by Glace Bay, is the largest we know of
1354 # (Glace Bay was perhaps not the best name choice but no point changing now).
1355 # Shanks & Pottenger also write that Liverpool, NS was the only town
1356 # in Canada to observe DST in 1971 but not 1970; for now we'll assume
1359 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1360 Rule Halifax 1916 only - Apr 1 0:00 1:00 D
1361 Rule Halifax 1916 only - Oct 1 0:00 0 S
1362 Rule Halifax 1920 only - May 9 0:00 1:00 D
1363 Rule Halifax 1920 only - Aug 29 0:00 0 S
1364 Rule Halifax 1921 only - May 6 0:00 1:00 D
1365 Rule Halifax 1921 1922 - Sep 5 0:00 0 S
1366 Rule Halifax 1922 only - Apr 30 0:00 1:00 D
1367 Rule Halifax 1923 1925 - May Sun>=1 0:00 1:00 D
1368 Rule Halifax 1923 only - Sep 4 0:00 0 S
1369 Rule Halifax 1924 only - Sep 15 0:00 0 S
1370 Rule Halifax 1925 only - Sep 28 0:00 0 S
1371 Rule Halifax 1926 only - May 16 0:00 1:00 D
1372 Rule Halifax 1926 only - Sep 13 0:00 0 S
1373 Rule Halifax 1927 only - May 1 0:00 1:00 D
1374 Rule Halifax 1927 only - Sep 26 0:00 0 S
1375 Rule Halifax 1928 1931 - May Sun>=8 0:00 1:00 D
1376 Rule Halifax 1928 only - Sep 9 0:00 0 S
1377 Rule Halifax 1929 only - Sep 3 0:00 0 S
1378 Rule Halifax 1930 only - Sep 15 0:00 0 S
1379 Rule Halifax 1931 1932 - Sep Mon>=24 0:00 0 S
1380 Rule Halifax 1932 only - May 1 0:00 1:00 D
1381 Rule Halifax 1933 only - Apr 30 0:00 1:00 D
1382 Rule Halifax 1933 only - Oct 2 0:00 0 S
1383 Rule Halifax 1934 only - May 20 0:00 1:00 D
1384 Rule Halifax 1934 only - Sep 16 0:00 0 S
1385 Rule Halifax 1935 only - Jun 2 0:00 1:00 D
1386 Rule Halifax 1935 only - Sep 30 0:00 0 S
1387 Rule Halifax 1936 only - Jun 1 0:00 1:00 D
1388 Rule Halifax 1936 only - Sep 14 0:00 0 S
1389 Rule Halifax 1937 1938 - May Sun>=1 0:00 1:00 D
1390 Rule Halifax 1937 1941 - Sep Mon>=24 0:00 0 S
1391 Rule Halifax 1939 only - May 28 0:00 1:00 D
1392 Rule Halifax 1940 1941 - May Sun>=1 0:00 1:00 D
1393 Rule Halifax 1946 1949 - Apr lastSun 2:00 1:00 D
1394 Rule Halifax 1946 1949 - Sep lastSun 2:00 0 S
1395 Rule Halifax 1951 1954 - Apr lastSun 2:00 1:00 D
1396 Rule Halifax 1951 1954 - Sep lastSun 2:00 0 S
1397 Rule Halifax 1956 1959 - Apr lastSun 2:00 1:00 D
1398 Rule Halifax 1956 1959 - Sep lastSun 2:00 0 S
1399 Rule Halifax 1962 1973 - Apr lastSun 2:00 1:00 D
1400 Rule Halifax 1962 1973 - Oct lastSun 2:00 0 S
1401 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1402 Zone America/Halifax -4:14:24 - LMT 1902 Jun 15
1403 -4:00 Halifax A%sT 1918
1404 -4:00 Canada A%sT 1919
1405 -4:00 Halifax A%sT 1942 Feb 9 2:00s
1406 -4:00 Canada A%sT 1946
1407 -4:00 Halifax A%sT 1974
1409 Zone America/Glace_Bay -3:59:48 - LMT 1902 Jun 15
1410 -4:00 Canada A%sT 1953
1411 -4:00 Halifax A%sT 1954
1413 -4:00 Halifax A%sT 1974
1418 # From Paul Eggert (2007-01-31):
1419 # The Time Definition Act <http://www.gnb.ca/0062/PDF-acts/t-06.pdf>
1420 # says they changed at 00:01 through 2006, and
1421 # <http://www.canlii.org/nb/laws/sta/t-6/20030127/whole.html> makes it
1422 # clear that this was the case since at least 1993.
1423 # For now, assume it started in 1993.
1425 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1426 Rule Moncton 1933 1935 - Jun Sun>=8 1:00 1:00 D
1427 Rule Moncton 1933 1935 - Sep Sun>=8 1:00 0 S
1428 Rule Moncton 1936 1938 - Jun Sun>=1 1:00 1:00 D
1429 Rule Moncton 1936 1938 - Sep Sun>=1 1:00 0 S
1430 Rule Moncton 1939 only - May 27 1:00 1:00 D
1431 Rule Moncton 1939 1941 - Sep Sat>=21 1:00 0 S
1432 Rule Moncton 1940 only - May 19 1:00 1:00 D
1433 Rule Moncton 1941 only - May 4 1:00 1:00 D
1434 Rule Moncton 1946 1972 - Apr lastSun 2:00 1:00 D
1435 Rule Moncton 1946 1956 - Sep lastSun 2:00 0 S
1436 Rule Moncton 1957 1972 - Oct lastSun 2:00 0 S
1437 Rule Moncton 1993 2006 - Apr Sun>=1 0:01 1:00 D
1438 Rule Moncton 1993 2006 - Oct lastSun 0:01 0 S
1439 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1440 Zone America/Moncton -4:19:08 - LMT 1883 Dec 9
1441 -5:00 - EST 1902 Jun 15
1442 -4:00 Canada A%sT 1933
1443 -4:00 Moncton A%sT 1942
1444 -4:00 Canada A%sT 1946
1445 -4:00 Moncton A%sT 1973
1446 -4:00 Canada A%sT 1993
1447 -4:00 Moncton A%sT 2007
1452 # From Paul Eggert (2015-03-24):
1453 # See America/Toronto for most of Quebec, including Montreal.
1455 # Matthews and Vincent (1998) also write that Quebec east of the -63
1456 # meridian is supposed to observe AST, but residents as far east as
1457 # Natashquan use EST/EDT, and residents east of Natashquan use AST.
1458 # The Quebec department of justice writes in
1459 # "The situation in Minganie and Basse-Côte-Nord"
1460 # http://www.justice.gouv.qc.ca/english/publications/generale/temps-minganie-a.htm
1461 # that the coastal strip from just east of Natashquan to Blanc-Sablon
1462 # observes Atlantic standard time all year round.
1463 # https://www.assnat.qc.ca/Media/Process.aspx?MediaId=ANQ.Vigie.Bll.DocumentGenerique_8845en
1464 # says this common practice was codified into law as of 2007.
1465 # For lack of better info, guess this practice began around 1970, contra to
1466 # Shanks & Pottenger who have this region observing AST/ADT.
1468 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1469 Zone America/Blanc-Sablon -3:48:28 - LMT 1884
1470 -4:00 Canada A%sT 1970
1475 # From Paul Eggert (2006-07-09):
1476 # Shanks & Pottenger write that since 1970 most of Ontario has been like
1478 # Thunder Bay skipped DST in 1973.
1479 # Many smaller locales did not observe peacetime DST until 1974;
1480 # Nipigon (EST) and Rainy River (CST) are the largest that we know of.
1481 # Far west Ontario is like Winnipeg; far east Quebec is like Halifax.
1483 # From Mark Brader (2003-07-26):
1484 # [According to the Toronto Star] Orillia, Ontario, adopted DST
1485 # effective Saturday, 1912-06-22, 22:00; the article mentions that
1486 # Port Arthur (now part of Thunder Bay, Ontario) as well as Moose Jaw
1487 # have already done so. In Orillia DST was to run until Saturday,
1488 # 1912-08-31 (no time mentioned), but it was met with considerable
1489 # hostility from certain segments of the public, and was revoked after
1490 # only two weeks - I copied it as Saturday, 1912-07-07, 22:00, but
1491 # presumably that should be -07-06. (1912-06-19, -07-12; also letters
1494 # Kenora, Ontario, was to abandon DST on 1914-06-01 (-05-21).
1496 # From Paul Eggert (2017-07-08):
1497 # For more on Orillia, see: Daubs K. Bold attempt at daylight saving
1498 # time became a comic failure in Orillia. Toronto Star 2017-07-08.
1499 # https://www.thestar.com/news/insight/2017/07/08/bold-attempt-at-daylight-saving-time-became-a-comic-failure-in-orillia.html
1501 # From Paul Eggert (1997-10-17):
1502 # Mark Brader writes that an article in the 1997-10-14 Toronto Star
1503 # says that Atikokan, Ontario currently does not observe DST,
1504 # but will vote on 11-10 whether to use EST/EDT.
1505 # He also writes that the Ontario Time Act (1990, Chapter T.9)
1506 # http://www.gov.on.ca/MBS/english/publications/statregs/conttext.html
1507 # says that Ontario east of 90W uses EST/EDT, and west of 90W uses CST/CDT.
1508 # Officially Atikokan is therefore on CST/CDT, and most likely this report
1509 # concerns a non-official time observed as a matter of local practice.
1511 # From Paul Eggert (2000-10-02):
1512 # Matthews and Vincent (1998) write that Atikokan, Pickle Lake, and
1513 # New Osnaburgh observe CST all year, that Big Trout Lake observes
1514 # CST/CDT, and that Upsala and Shebandowan observe EST/EDT, all in
1515 # violation of the official Ontario rules.
1517 # From Paul Eggert (2006-07-09):
1518 # Chris Walton (2006-07-06) mentioned an article by Stephanie MacLellan in the
1519 # 2005-07-21 Chronicle-Journal, which said:
1521 # The clocks in Atikokan stay set on standard time year-round.
1522 # This means they spend about half the time on central time and
1523 # the other half on eastern time.
1525 # For the most part, the system works, Mayor Dennis Brown said.
1527 # "The majority of businesses in Atikokan deal more with Eastern
1528 # Canada, but there are some that deal with Western Canada," he
1529 # said. "I don't see any changes happening here."
1531 # Walton also writes "Supposedly Pickle Lake and Mishkeegogamang
1532 # [New Osnaburgh] follow the same practice."
1534 # From Garry McKinnon (2006-07-14) via Chris Walton:
1535 # I chatted with a member of my board who has an outstanding memory
1536 # and a long history in Atikokan (and in the telecom industry) and he
1537 # can say for certain that Atikokan has been practicing the current
1538 # time keeping since 1952, at least.
1540 # From Paul Eggert (2006-07-17):
1541 # Shanks & Pottenger say that Atikokan has agreed with Rainy River
1542 # ever since standard time was introduced, but the information from
1543 # McKinnon sounds more authoritative. For now, assume that Atikokan
1544 # switched to EST immediately after WWII era daylight saving time
1545 # ended. This matches the old (less-populous) America/Coral_Harbour
1546 # entry since our cutoff date of 1970, so we can move
1547 # America/Coral_Harbour to the 'backward' file.
1549 # From Mark Brader (2010-03-06):
1551 # Currently the database has:
1555 # # From Paul Eggert (2006-07-09):
1556 # # Shanks & Pottenger write that since 1970 most of Ontario has been like
1558 # # Thunder Bay skipped DST in 1973.
1559 # # Many smaller locales did not observe peacetime DST until 1974;
1560 # # Nipigon (EST) and Rainy River (CST) are the largest that we know of.
1562 # In the (Toronto) Globe and Mail for Saturday, 1955-09-24, in the bottom
1563 # right corner of page 1, it says that Toronto will return to standard
1564 # time at 2 am Sunday morning (which agrees with the database), and that:
1566 # The one-hour setback will go into effect throughout most of Ontario,
1567 # except in areas like Windsor which remains on standard time all year.
1569 # Windsor is, of course, a lot larger than Nipigon.
1571 # I only came across this incidentally. I don't know if Windsor began
1572 # observing DST when Detroit did, or in 1974, or on some other date.
1574 # By the way, the article continues by noting that:
1576 # Some cities in the United States have pushed the deadline back
1577 # three weeks and will change over from daylight saving in October.
1579 # From Arthur David Olson (2010-07-17):
1581 # "Standard Time and Time Zones in Canada" appeared in
1582 # The Journal of The Royal Astronomical Society of Canada,
1583 # volume 26, number 2 (February 1932) and, as of 2010-07-17,
1585 # http://adsabs.harvard.edu/full/1932JRASC..26...49S
1587 # It includes the text below (starting on page 57):
1589 # A list of the places in Canada using daylight saving time would
1590 # require yearly revision. From information kindly furnished by
1591 # the provincial governments and by the postmasters in many cities
1592 # and towns, it is found that the following places used daylight sav-
1593 # ing in 1930. The information for the province of Quebec is definite,
1594 # for the other provinces only approximate:
1596 # Province Daylight saving time used
1597 # Prince Edward Island Not used.
1598 # Nova Scotia In Halifax only.
1599 # New Brunswick In St. John only.
1600 # Quebec In the following places:
1604 # St. Lambert Cap de la Madelèine
1605 # Verdun Loretteville
1606 # Westmount Richmond
1607 # Outremont St. Jérôme
1608 # Longueuil Greenfield Park
1610 # Chambly-Canton Beaulieu
1611 # Melbourne La Tuque
1612 # St. Théophile Buckingham
1613 # Ontario Used generally in the cities and towns along
1614 # the southerly part of the province. Not
1615 # used in the northwesterly part.
1616 # Manitoba Not used.
1617 # Saskatchewan In Regina only.
1619 # British Columbia Not used.
1621 # With some exceptions, the use of daylight saving may be said to be limited
1622 # to those cities and towns lying between Quebec city and Windsor, Ont.
1624 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1625 Rule Toronto 1919 only - Mar 30 23:30 1:00 D
1626 Rule Toronto 1919 only - Oct 26 0:00 0 S
1627 Rule Toronto 1920 only - May 2 2:00 1:00 D
1628 Rule Toronto 1920 only - Sep 26 0:00 0 S
1629 Rule Toronto 1921 only - May 15 2:00 1:00 D
1630 Rule Toronto 1921 only - Sep 15 2:00 0 S
1631 Rule Toronto 1922 1923 - May Sun>=8 2:00 1:00 D
1632 # Shanks & Pottenger say 1923-09-19; assume it's a typo and that "-16"
1634 Rule Toronto 1922 1926 - Sep Sun>=15 2:00 0 S
1635 Rule Toronto 1924 1927 - May Sun>=1 2:00 1:00 D
1636 # The 1927-to-1939 rules can be expressed more simply as
1637 # Rule Toronto 1927 1937 - Sep Sun>=25 2:00 0 S
1638 # Rule Toronto 1928 1937 - Apr Sun>=25 2:00 1:00 D
1639 # Rule Toronto 1938 1940 - Apr lastSun 2:00 1:00 D
1640 # Rule Toronto 1938 1939 - Sep lastSun 2:00 0 S
1641 # The rules below avoid use of Sun>=25
1642 # (which pre-2004 versions of zic cannot handle).
1643 Rule Toronto 1927 1932 - Sep lastSun 2:00 0 S
1644 Rule Toronto 1928 1931 - Apr lastSun 2:00 1:00 D
1645 Rule Toronto 1932 only - May 1 2:00 1:00 D
1646 Rule Toronto 1933 1940 - Apr lastSun 2:00 1:00 D
1647 Rule Toronto 1933 only - Oct 1 2:00 0 S
1648 Rule Toronto 1934 1939 - Sep lastSun 2:00 0 S
1649 Rule Toronto 1945 1946 - Sep lastSun 2:00 0 S
1650 Rule Toronto 1946 only - Apr lastSun 2:00 1:00 D
1651 Rule Toronto 1947 1949 - Apr lastSun 0:00 1:00 D
1652 Rule Toronto 1947 1948 - Sep lastSun 0:00 0 S
1653 Rule Toronto 1949 only - Nov lastSun 0:00 0 S
1654 Rule Toronto 1950 1973 - Apr lastSun 2:00 1:00 D
1655 Rule Toronto 1950 only - Nov lastSun 2:00 0 S
1656 Rule Toronto 1951 1956 - Sep lastSun 2:00 0 S
1657 # Shanks & Pottenger say Toronto ended DST a week early in 1971,
1658 # namely on 1971-10-24, but Mark Brader wrote (2003-05-31) that this
1659 # is wrong, and that he had confirmed it by checking the 1971-10-30
1660 # Toronto Star, which said that DST was ending 1971-10-31 as usual.
1661 Rule Toronto 1957 1973 - Oct lastSun 2:00 0 S
1663 # From Paul Eggert (2003-07-27):
1664 # Willett (1914-03) writes (p. 17) "In the Cities of Fort William, and
1665 # Port Arthur, Ontario, the principle of the Bill has been in
1666 # operation for the past three years, and in the City of Moose Jaw,
1667 # Saskatchewan, for one year."
1669 # From David Bryan via Tory Tronrud, Director/Curator,
1670 # Thunder Bay Museum (2003-11-12):
1671 # There is some suggestion, however, that, by-law or not, daylight
1672 # savings time was being practiced in Fort William and Port Arthur
1673 # before 1909.... [I]n 1910, the line between the Eastern and Central
1674 # Time Zones was permanently moved about two hundred miles west to
1675 # include the Thunder Bay area.... When Canada adopted daylight
1676 # savings time in 1916, Fort William and Port Arthur, having done so
1677 # already, did not change their clocks.... During the Second World
1678 # War,... [t]he cities agreed to implement DST during the summer
1679 # months for the remainder of the war years.
1681 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1682 Zone America/Toronto -5:17:32 - LMT 1895
1683 -5:00 Canada E%sT 1919
1684 -5:00 Toronto E%sT 1942 Feb 9 2:00s
1685 -5:00 Canada E%sT 1946
1686 -5:00 Toronto E%sT 1974
1688 Zone America/Thunder_Bay -5:57:00 - LMT 1895
1691 -5:00 Canada E%sT 1970
1692 -5:00 Toronto E%sT 1973
1695 Zone America/Nipigon -5:53:04 - LMT 1895
1696 -5:00 Canada E%sT 1940 Sep 29
1697 -5:00 1:00 EDT 1942 Feb 9 2:00s
1699 Zone America/Rainy_River -6:18:16 - LMT 1895
1700 -6:00 Canada C%sT 1940 Sep 29
1701 -6:00 1:00 CDT 1942 Feb 9 2:00s
1703 Zone America/Atikokan -6:06:28 - LMT 1895
1704 -6:00 Canada C%sT 1940 Sep 29
1705 -6:00 1:00 CDT 1942 Feb 9 2:00s
1706 -6:00 Canada C%sT 1945 Sep 30 2:00
1712 # From Rob Douglas (2006-04-06):
1713 # the old Manitoba Time Act - as amended by Bill 2, assented to
1714 # March 27, 1987 ... said ...
1715 # "between two o'clock Central Standard Time in the morning of
1716 # the first Sunday of April of each year and two o'clock Central
1717 # Standard Time in the morning of the last Sunday of October next
1718 # following, one hour in advance of Central Standard Time."...
1719 # I believe that the English legislation [of the old time act] had
1720 # been assented to (March 22, 1967)....
1721 # Also, as far as I can tell, there was no order-in-council varying
1722 # the time of Daylight Saving Time for 2005 and so the provisions of
1723 # the 1987 version would apply - the changeover was at 2:00 Central
1724 # Standard Time (i.e. not until 3:00 Central Daylight Time).
1726 # From Paul Eggert (2006-04-10):
1727 # Shanks & Pottenger say Manitoba switched at 02:00 (not 02:00s)
1728 # starting 1966. Since 02:00s is clearly correct for 1967 on, assume
1729 # it was also 02:00s in 1966.
1731 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1732 Rule Winn 1916 only - Apr 23 0:00 1:00 D
1733 Rule Winn 1916 only - Sep 17 0:00 0 S
1734 Rule Winn 1918 only - Apr 14 2:00 1:00 D
1735 Rule Winn 1918 only - Oct 27 2:00 0 S
1736 Rule Winn 1937 only - May 16 2:00 1:00 D
1737 Rule Winn 1937 only - Sep 26 2:00 0 S
1738 Rule Winn 1942 only - Feb 9 2:00 1:00 W # War
1739 Rule Winn 1945 only - Aug 14 23:00u 1:00 P # Peace
1740 Rule Winn 1945 only - Sep lastSun 2:00 0 S
1741 Rule Winn 1946 only - May 12 2:00 1:00 D
1742 Rule Winn 1946 only - Oct 13 2:00 0 S
1743 Rule Winn 1947 1949 - Apr lastSun 2:00 1:00 D
1744 Rule Winn 1947 1949 - Sep lastSun 2:00 0 S
1745 Rule Winn 1950 only - May 1 2:00 1:00 D
1746 Rule Winn 1950 only - Sep 30 2:00 0 S
1747 Rule Winn 1951 1960 - Apr lastSun 2:00 1:00 D
1748 Rule Winn 1951 1958 - Sep lastSun 2:00 0 S
1749 Rule Winn 1959 only - Oct lastSun 2:00 0 S
1750 Rule Winn 1960 only - Sep lastSun 2:00 0 S
1751 Rule Winn 1963 only - Apr lastSun 2:00 1:00 D
1752 Rule Winn 1963 only - Sep 22 2:00 0 S
1753 Rule Winn 1966 1986 - Apr lastSun 2:00s 1:00 D
1754 Rule Winn 1966 2005 - Oct lastSun 2:00s 0 S
1755 Rule Winn 1987 2005 - Apr Sun>=1 2:00s 1:00 D
1756 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1757 Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16
1758 -6:00 Winn C%sT 2006
1764 # From Mark Brader (2003-07-26):
1765 # The first actual adoption of DST in Canada was at the municipal
1766 # level. As the [Toronto] Star put it (1912-06-07), "While people
1767 # elsewhere have long been talking of legislation to save daylight,
1768 # the city of Moose Jaw [Saskatchewan] has acted on its own hook."
1769 # DST in Moose Jaw began on Saturday, 1912-06-01 (no time mentioned:
1770 # presumably late evening, as below), and would run until "the end of
1771 # the summer". The discrepancy between municipal time and railroad
1774 # From Paul Eggert (2003-07-27):
1775 # Willett (1914-03) notes that DST "has been in operation ... in the
1776 # City of Moose Jaw, Saskatchewan, for one year."
1778 # From Paul Eggert (2006-03-22):
1779 # Shanks & Pottenger say that since 1970 this region has mostly been as Regina.
1780 # Some western towns (e.g. Swift Current) switched from MST/MDT to CST in 1972.
1781 # Other western towns (e.g. Lloydminster) are like Edmonton.
1782 # Matthews and Vincent (1998) write that Denare Beach and Creighton
1783 # are like Winnipeg, in violation of Saskatchewan law.
1785 # From W. Jones (1992-11-06):
1786 # The. . .below is based on information I got from our law library, the
1787 # provincial archives, and the provincial Community Services department.
1788 # A precise history would require digging through newspaper archives, and
1789 # since you didn't say what you wanted, I didn't bother.
1791 # Saskatchewan is split by a time zone meridian (105W) and over the years
1792 # the boundary became pretty ragged as communities near it reevaluated
1793 # their affiliations in one direction or the other. In 1965 a provincial
1794 # referendum favoured legislating common time practices.
1796 # On 15 April 1966 the Time Act (c. T-14, Revised Statutes of
1797 # Saskatchewan 1978) was proclaimed, and established that the eastern
1798 # part of Saskatchewan would use CST year round, that districts in
1799 # northwest Saskatchewan would by default follow CST but could opt to
1800 # follow Mountain Time rules (thus 1 hour difference in the winter and
1801 # zero in the summer), and that districts in southwest Saskatchewan would
1802 # by default follow MT but could opt to follow CST.
1804 # It took a few years for the dust to settle (I know one story of a town
1805 # on one time zone having its school in another, such that a mom had to
1806 # serve her family lunch in two shifts), but presently it seems that only
1807 # a few towns on the border with Alberta (e.g. Lloydminster) follow MT
1808 # rules any more; all other districts appear to have used CST year round
1809 # since sometime in the 1960s.
1811 # From Chris Walton (2006-06-26):
1812 # The Saskatchewan time act which was last updated in 1996 is about 30 pages
1813 # long and rather painful to read.
1814 # http://www.qp.gov.sk.ca/documents/English/Statutes/Statutes/T14.pdf
1816 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1817 Rule Regina 1918 only - Apr 14 2:00 1:00 D
1818 Rule Regina 1918 only - Oct 27 2:00 0 S
1819 Rule Regina 1930 1934 - May Sun>=1 0:00 1:00 D
1820 Rule Regina 1930 1934 - Oct Sun>=1 0:00 0 S
1821 Rule Regina 1937 1941 - Apr Sun>=8 0:00 1:00 D
1822 Rule Regina 1937 only - Oct Sun>=8 0:00 0 S
1823 Rule Regina 1938 only - Oct Sun>=1 0:00 0 S
1824 Rule Regina 1939 1941 - Oct Sun>=8 0:00 0 S
1825 Rule Regina 1942 only - Feb 9 2:00 1:00 W # War
1826 Rule Regina 1945 only - Aug 14 23:00u 1:00 P # Peace
1827 Rule Regina 1945 only - Sep lastSun 2:00 0 S
1828 Rule Regina 1946 only - Apr Sun>=8 2:00 1:00 D
1829 Rule Regina 1946 only - Oct Sun>=8 2:00 0 S
1830 Rule Regina 1947 1957 - Apr lastSun 2:00 1:00 D
1831 Rule Regina 1947 1957 - Sep lastSun 2:00 0 S
1832 Rule Regina 1959 only - Apr lastSun 2:00 1:00 D
1833 Rule Regina 1959 only - Oct lastSun 2:00 0 S
1835 Rule Swift 1957 only - Apr lastSun 2:00 1:00 D
1836 Rule Swift 1957 only - Oct lastSun 2:00 0 S
1837 Rule Swift 1959 1961 - Apr lastSun 2:00 1:00 D
1838 Rule Swift 1959 only - Oct lastSun 2:00 0 S
1839 Rule Swift 1960 1961 - Sep lastSun 2:00 0 S
1840 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1841 Zone America/Regina -6:58:36 - LMT 1905 Sep
1842 -7:00 Regina M%sT 1960 Apr lastSun 2:00
1844 Zone America/Swift_Current -7:11:20 - LMT 1905 Sep
1845 -7:00 Canada M%sT 1946 Apr lastSun 2:00
1846 -7:00 Regina M%sT 1950
1847 -7:00 Swift M%sT 1972 Apr lastSun 2:00
1853 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1854 Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D
1855 Rule Edm 1918 only - Oct 27 2:00 0 S
1856 Rule Edm 1919 only - May 27 2:00 0 S
1857 Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D
1858 Rule Edm 1920 only - Oct lastSun 2:00 0 S
1859 Rule Edm 1921 1923 - Sep lastSun 2:00 0 S
1860 Rule Edm 1942 only - Feb 9 2:00 1:00 W # War
1861 Rule Edm 1945 only - Aug 14 23:00u 1:00 P # Peace
1862 Rule Edm 1945 only - Sep lastSun 2:00 0 S
1863 Rule Edm 1947 only - Apr lastSun 2:00 1:00 D
1864 Rule Edm 1947 only - Sep lastSun 2:00 0 S
1865 Rule Edm 1967 only - Apr lastSun 2:00 1:00 D
1866 Rule Edm 1967 only - Oct lastSun 2:00 0 S
1867 Rule Edm 1969 only - Apr lastSun 2:00 1:00 D
1868 Rule Edm 1969 only - Oct lastSun 2:00 0 S
1869 Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D
1870 Rule Edm 1972 2006 - Oct lastSun 2:00 0 S
1871 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1872 Zone America/Edmonton -7:33:52 - LMT 1906 Sep
1879 # From Paul Eggert (2006-03-22):
1880 # Shanks & Pottenger write that since 1970 most of this region has
1881 # been like Vancouver.
1882 # Dawson Creek uses MST. Much of east BC is like Edmonton.
1883 # Matthews and Vincent (1998) write that Creston is like Dawson Creek.
1885 # It seems though that (re: Creston) is not entirely correct:
1887 # From Chris Walton (2011-12-01):
1888 # There are two areas within the Canadian province of British Columbia
1889 # that do not currently observe daylight saving:
1890 # a) The Creston Valley (includes the town of Creston and surrounding area)
1891 # b) The eastern half of the Peace River Regional District
1892 # (includes the cities of Dawson Creek and Fort St. John)
1894 # Earlier this year I stumbled across a detailed article about the time
1895 # keeping history of Creston; it was written by Tammy Hardwick who is the
1896 # manager of the Creston & District Museum. The article was written in May 2009.
1897 # http://www.ilovecreston.com/?p=articles&t=spec&ar=260
1898 # According to the article, Creston has not changed its clocks since June 1918.
1899 # i.e. Creston has been stuck on UTC-7 for 93 years.
1900 # Dawson Creek, on the other hand, changed its clocks as recently as April 1972.
1902 # Unfortunately the exact date for the time change in June 1918 remains
1903 # unknown and will be difficult to ascertain. I e-mailed Tammy a few months
1904 # ago to ask if Sunday June 2 was a reasonable guess. She said it was just
1905 # as plausible as any other date (in June). She also said that after writing
1906 # the article she had discovered another time change in 1916; this is the
1907 # subject of another article which she wrote in October 2010.
1908 # http://www.creston.museum.bc.ca/index.php?module=comments&uop=view_comment&cm+id=56
1910 # Here is a summary of the three clock change events in Creston's history:
1911 # 1. 1884 or 1885: adoption of Mountain Standard Time (GMT-7)
1912 # Exact date unknown
1913 # 2. Oct 1916: switch to Pacific Standard Time (GMT-8)
1914 # Exact date in October unknown; Sunday October 1 is a reasonable guess.
1915 # 3. June 1918: switch to Pacific Daylight Time (GMT-7)
1916 # Exact date in June unknown; Sunday June 2 is a reasonable guess.
1918 # On Oct 27/1918 when daylight saving ended in the rest of Canada,
1919 # Creston did not change its clocks.
1921 # During WWII when the Federal Government legislated a mandatory clock change,
1922 # Creston did not oblige.
1924 # There is no guarantee that Creston will remain on Mountain Standard Time
1926 # The subject was debated at least once this year by the town Council.
1927 # http://www.bclocalnews.com/kootenay_rockies/crestonvalleyadvance/news/116760809.html
1929 # During a period WWII, summer time (Daylight saying) was mandatory in Canada.
1930 # In Creston, that was handled by shifting the area to PST (-8:00) then applying
1931 # summer time to cause the offset to be -7:00, the same as it had been before
1932 # the change. It can be argued that the timezone abbreviation during this
1933 # period should be PDT rather than MST, but that doesn't seem important enough
1934 # (to anyone) to further complicate the rules.
1936 # The transition dates (and times) are guesses.
1938 # From Matt Johnson (2015-09-21):
1939 # Fort Nelson, BC, Canada will cancel DST this year. So while previously they
1940 # were aligned with America/Vancouver, they're now aligned with
1941 # America/Dawson_Creek.
1942 # http://www.northernrockies.ca/EN/meta/news/archives/2015/northern-rockies-time-change.html
1944 # From Tim Parenti (2015-09-23):
1945 # This requires a new zone for the Northern Rockies Regional Municipality,
1946 # America/Fort_Nelson. The resolution of 2014-12-08 was reached following a
1947 # 2014-11-15 poll with nearly 75% support. Effectively, the municipality has
1948 # been on MST (-0700) like Dawson Creek since it advanced its clocks on
1951 # From Paul Eggert (2015-09-23):
1952 # Shanks says Fort Nelson did not observe DST in 1946, unlike Vancouver.
1954 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1955 Rule Vanc 1918 only - Apr 14 2:00 1:00 D
1956 Rule Vanc 1918 only - Oct 27 2:00 0 S
1957 Rule Vanc 1942 only - Feb 9 2:00 1:00 W # War
1958 Rule Vanc 1945 only - Aug 14 23:00u 1:00 P # Peace
1959 Rule Vanc 1945 only - Sep 30 2:00 0 S
1960 Rule Vanc 1946 1986 - Apr lastSun 2:00 1:00 D
1961 Rule Vanc 1946 only - Oct 13 2:00 0 S
1962 Rule Vanc 1947 1961 - Sep lastSun 2:00 0 S
1963 Rule Vanc 1962 2006 - Oct lastSun 2:00 0 S
1964 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1965 Zone America/Vancouver -8:12:28 - LMT 1884
1966 -8:00 Vanc P%sT 1987
1968 Zone America/Dawson_Creek -8:00:56 - LMT 1884
1969 -8:00 Canada P%sT 1947
1970 -8:00 Vanc P%sT 1972 Aug 30 2:00
1972 Zone America/Fort_Nelson -8:10:47 - LMT 1884
1973 -8:00 Vanc P%sT 1946
1975 -8:00 Vanc P%sT 1987
1976 -8:00 Canada P%sT 2015 Mar 8 2:00
1978 Zone America/Creston -7:46:04 - LMT 1884
1979 -7:00 - MST 1916 Oct 1
1980 -8:00 - PST 1918 Jun 2
1983 # Northwest Territories, Nunavut, Yukon
1985 # From Paul Eggert (2006-03-22):
1986 # Dawson switched to PST in 1973. Inuvik switched to MST in 1979.
1987 # Mathew Englander (1996-10-07) gives the following refs:
1988 # * 1967. Paragraph 28(34)(g) of the Interpretation Act, S.C. 1967-68,
1989 # c. 7 defines Yukon standard time as UTC-9....
1990 # see Interpretation Act, R.S.C. 1985, c. I-21, s. 35(1).
1991 # [https://www.canlii.org/en/ca/laws/stat/rsc-1985-c-i-21/latest/rsc-1985-c-i-21.html]
1992 # * C.O. 1973/214 switched Yukon to PST on 1973-10-28 00:00.
1993 # * O.I.C. 1980/02 established DST.
1994 # * O.I.C. 1987/056 changed DST to Apr firstSun 2:00 to Oct lastSun 2:00.
1996 # From Brian Inglis (2015-04-14):
1998 # I tried to trace the history of Yukon time and found the following
1999 # regulations, giving the reference title and URL if found, regulation name,
2000 # and relevant quote if available. Each regulation specifically revokes its
2001 # predecessor. The final reference is to the current Interpretation Act
2002 # authorizing and resulting from these regulatory changes.
2004 # Only recent regulations were retrievable via Yukon government site search or
2005 # index, and only some via Canadian legal sources. Other sources used include
2006 # articles titled "Standard Time and Time Zones in Canada" from JRASC via ADS
2007 # Abstracts, cited by ADO for 1932 ..., and updated versions from 1958 and
2008 # 1970 quoted below; each article includes current extracts from provincial
2009 # and territorial ST and DST regulations at the end, summaries and details of
2010 # standard times and daylight saving time at many locations across Canada,
2011 # with time zone maps, tables and calculations for Canadian Sunrise, Sunset,
2012 # and LMST; they also cover many countries and global locations, with a chart
2013 # and table showing current Universal Time offsets, and may be useful as
2014 # another source of information for 1970 and earlier.
2016 # * Standard Time and Time Zones in Canada; Smith, C.C.; JRASC, Vol. 26,
2017 # pp.49-77; February 1932; SAO/NASA Astrophysics Data System (ADS)
2018 # http://adsabs.harvard.edu/abs/1932JRASC..26...49S from p.75:
2019 # Yukon Interpretation Ordinance
2020 # Yukon standard time is the local mean time at the one hundred and
2021 # thirty-fifth meridian.
2023 # * Standard Time and Time Zones in Canada; Smith, C.C.; Thomson, Malcolm M.;
2024 # JRASC, Vol. 52, pp.193-223; October 1958; SAO/NASA Astrophysics Data System
2025 # (ADS) http://adsabs.harvard.edu/abs/1958JRASC..52..193S from pp.220-1:
2026 # Yukon Interpretation Ordinance, 1955, Chap. 16.
2028 # (1) Subject to this section, standard time shall be reckoned as nine
2029 # hours behind Greenwich Time and called Yukon Standard Time.
2031 # (2) Notwithstanding subsection (1), the Commissioner may make regulations
2032 # varying the manner of reckoning standard time.
2034 # * Yukon Territory Commissioner's Order 1966-20 Interpretation Ordinance
2035 # http://? - no online source found
2037 # * Standard Time and Time Zones in Canada; Thomson, Malcolm M.; JRASC,
2038 # Vol. 64, pp.129-162; June 1970; SAO/NASA Astrophysics Data System (ADS)
2039 # http://adsabs.harvard.edu/abs/1970JRASC..64..129T from p.156: Yukon
2040 # Territory Commissioner's Order 1967-59 Interpretation Ordinance ...
2042 # 1. Commissioner's Order 1966-20 dated at Whitehorse in the Yukon
2043 # Territory on 27th January, 1966, is hereby revoked.
2045 # 2. Yukon (East) Standard Time as defined by section 36 of the
2046 # Interpretation Ordinance from and after mid-night on the 28th day of May,
2047 # 1967 shall be reckoned in the same manner as Pacific Standard Time, that
2048 # is to say, eight hours behind Greenwich Time in the area of the Yukon
2049 # Territory lying east of the 138th degree longitude west.
2051 # 3. In the remainder of the Territory, lying west of the 138th degree
2052 # longitude west, Yukon (West) Standard Time shall be reckoned as nine
2053 # hours behind Greenwich Time.
2055 # * Yukon Standard Time defined as Pacific Standard Time, YCO 1973/214
2056 # https://www.canlii.org/en/yk/laws/regu/yco-1973-214/latest/yco-1973-214.html
2057 # C.O. 1973/214 INTERPRETATION ACT ...
2059 # 1. Effective October 28, 1973 Commissioner's Order 1967/59 is hereby
2062 # 2. Yukon Standard Time as defined by section 36 of the Interpretation
2063 # Act from and after midnight on the twenty-eighth day of October, 1973
2064 # shall be reckoned in the same manner as Pacific Standard Time, that is
2065 # to say eight hours behind Greenwich Time.
2067 # * O.I.C. 1980/02 INTERPRETATION ACT
2068 # http://? - no online source found
2070 # * Yukon Daylight Saving Time, YOIC 1987/56
2071 # https://www.canlii.org/en/yk/laws/regu/yoic-1987-56/latest/yoic-1987-56.html
2072 # O.I.C. 1987/056 INTERPRETATION ACT ...
2074 # In every year between
2075 # (a) two o'clock in the morning in the first Sunday in April, and
2076 # (b) two o'clock in the morning in the last Sunday in October,
2077 # Standard Time shall be reckoned as seven hours behind Greenwich Time and
2078 # called Yukon Daylight Saving Time.
2080 # Dated ... 9th day of March, A.D., 1987.
2082 # * Yukon Daylight Saving Time 2006, YOIC 2006/127
2083 # https://www.canlii.org/en/yk/laws/regu/yoic-2006-127/latest/yoic-2006-127.html
2084 # O.I.C. 2006/127 INTERPRETATION ACT ...
2086 # 1. In Yukon each year the time for general purposes shall be 7 hours
2087 # behind Greenwich mean time during the period commencing at two o'clock
2088 # in the forenoon on the second Sunday of March and ending at two o'clock
2089 # in the forenoon on the first Sunday of November and shall be called
2090 # Yukon Daylight Saving Time.
2092 # 2. Order-in-Council 1987/56 is revoked.
2094 # 3. This order comes into force January 1, 2007.
2096 # * Interpretation Act, RSY 2002, c 125
2097 # https://www.canlii.org/en/yk/laws/stat/rsy-2002-c-125/latest/rsy-2002-c-125.html
2099 # From Rives McDow (1999-09-04):
2100 # Nunavut ... moved ... to incorporate the whole territory into one time zone.
2101 # Nunavut moves to single time zone Oct. 31
2102 # http://www.nunatsiaq.com/nunavut/nvt90903_13.html
2104 # From Antoine Leca (1999-09-06):
2105 # We then need to create a new timezone for the Kitikmeot region of Nunavut
2106 # to differentiate it from the Yellowknife region.
2108 # From Paul Eggert (1999-09-20):
2109 # Basic Facts: The New Territory
2110 # http://www.nunavut.com/basicfacts/english/basicfacts_1territory.html
2111 # (1999) reports that Pangnirtung operates on eastern time,
2112 # and that Coral Harbour does not observe DST. We don't know when
2113 # Pangnirtung switched to eastern time; we'll guess 1995.
2115 # From Rives McDow (1999-11-08):
2116 # On October 31, when the rest of Nunavut went to Central time,
2117 # Pangnirtung wobbled. Here is the result of their wobble:
2119 # The following businesses and organizations in Pangnirtung use Central Time:
2121 # First Air, Power Corp, Nunavut Construction, Health Center, RCMP,
2122 # Eastern Arctic National Parks, A & D Specialist
2124 # The following businesses and organizations in Pangnirtung use Eastern Time:
2126 # Hamlet office, All other businesses, Both schools, Airport operator
2128 # This has made for an interesting situation there, which warranted the news.
2129 # No one there that I spoke with seems concerned, or has plans to
2130 # change the local methods of keeping time, as it evidently does not
2131 # really interfere with any activities or make things difficult locally.
2132 # They plan to celebrate New Year's turn-over twice, one hour apart,
2133 # so it appears that the situation will last at least that long.
2134 # The Nunavut Intergovernmental Affairs hopes that they will "come to
2135 # their senses", but the locals evidently don't see any problem with
2136 # the current state of affairs.
2138 # From Michaela Rodrigue, writing in the
2139 # Nunatsiaq News (1999-11-19):
2140 # http://www.nunatsiaqonline.ca/archives/nunavut991130/nvt91119_17.html
2141 # Clyde River, Pangnirtung and Sanikiluaq now operate with two time zones,
2142 # central - or Nunavut time - for government offices, and eastern time
2143 # for municipal offices and schools.... Igloolik [was similar but then]
2144 # made the switch to central time on Saturday, Nov. 6.
2146 # From Paul Eggert (2000-10-02):
2147 # Matthews and Vincent (1998) say the following, but we lack histories
2148 # for these potential new Zones.
2150 # The Canadian Forces station at Alert uses Eastern Time while the
2151 # handful of residents at the Eureka weather station [in the Central
2152 # zone] skip daylight savings. Baffin Island, which is crossed by the
2153 # Central, Eastern and Atlantic Time zones only uses Eastern Time.
2154 # Gjoa Haven, Taloyoak and Pelly Bay all use Mountain instead of
2155 # Central Time and Southampton Island [in the Central zone] is not
2156 # required to use daylight savings.
2158 # From <http://www.nunatsiaqonline.ca/archives/nunavut001130/nvt21110_02.html>
2159 # Nunavut now has two time zones (2000-11-10):
2160 # The Nunavut government would allow its employees in Kugluktuk and
2161 # Cambridge Bay to operate on central time year-round, putting them
2162 # one hour behind the rest of Nunavut for six months during the winter.
2163 # At the end of October the two communities had rebelled against
2164 # Nunavut's unified time zone, refusing to shift to eastern time with
2165 # the rest of the territory for the winter. Cambridge Bay remained on
2166 # central time, while Kugluktuk, even farther west, reverted to
2167 # mountain time, which they had used before the advent of Nunavut's
2168 # unified time zone in 1999.
2170 # From Rives McDow (2001-01-20), quoting the Nunavut government:
2171 # The preceding decision came into effect at midnight, Saturday Nov 4, 2000.
2173 # From Paul Eggert (2000-12-04):
2174 # Let's just keep track of the official times for now.
2176 # From Rives McDow (2001-03-07):
2177 # The premier of Nunavut has issued a ministerial statement advising
2178 # that effective 2001-04-01, the territory of Nunavut will revert
2179 # back to three time zones (mountain, central, and eastern). Of the
2180 # cities in Nunavut, Coral Harbor is the only one that I know of that
2181 # has said it will not observe dst, staying on EST year round. I'm
2182 # checking for more info, and will get back to you if I come up with
2184 # [Also see <http://www.nunatsiaq.com/nunavut/nvt10309_06.html> (2001-03-09).]
2186 # From Gwillim Law (2005-05-21):
2188 # http://www.canadiangeographic.ca/Magazine/SO98/geomap.asp
2189 # (from a 1998 Canadian Geographic article), the de facto and de jure time
2190 # for Southampton Island (at the north end of Hudson Bay) is UTC-5 all year
2191 # round. Using Google, it's easy to find other websites that confirm this.
2192 # I wasn't able to find how far back this time regimen goes, but since it
2193 # predates the creation of Nunavut, it probably goes back many years....
2194 # The Inuktitut name of Coral Harbour is Sallit, but it's rarely used.
2196 # From Paul Eggert (2014-10-17):
2197 # For lack of better information, assume that Southampton Island observed
2198 # daylight saving only during wartime. Gwillim Law's email also
2199 # mentioned maps now maintained by National Research Council Canada;
2200 # see above for an up-to-date link.
2202 # From Chris Walton (2007-03-01):
2203 # ... the community of Resolute (located on Cornwallis Island in
2204 # Nunavut) moved from Central Time to Eastern Time last November.
2205 # Basically the community did not change its clocks at the end of
2206 # daylight saving....
2207 # http://www.nnsl.com/frames/newspapers/2006-11/nov13_06none.html
2209 # From Chris Walton (2011-03-21):
2210 # Back in 2007 I initiated the creation of a new "zone file" for Resolute
2211 # Bay. Resolute Bay is a small community located about 900km north of
2212 # the Arctic Circle. The zone file was required because Resolute Bay had
2213 # decided to use UTC-5 instead of UTC-6 for the winter of 2006-2007.
2215 # According to new information which I received last week, Resolute Bay
2216 # went back to using UTC-6 in the winter of 2007-2008...
2218 # On March 11/2007 most of Canada went onto daylight saving. On March
2219 # 14/2007 I phoned the Resolute Bay hamlet office to do a "time check." I
2220 # talked to somebody that was both knowledgeable and helpful. I was able
2221 # to confirm that Resolute Bay was still operating on UTC-5. It was
2222 # explained to me that Resolute Bay had been on the Eastern Time zone
2223 # (EST) in the winter, and was now back on the Central Time zone (CDT).
2224 # i.e. the time zone had changed twice in the last year but the clocks
2225 # had not moved. The residents had to know which time zone they were in
2226 # so they could follow the correct TV schedule...
2228 # On Nov 02/2008 most of Canada went onto standard time. On Nov 03/2008 I
2229 # phoned the Resolute Bay hamlet office...[D]ue to the challenging nature
2230 # of the phone call, I decided to seek out an alternate source of
2231 # information. I found an e-mail address for somebody by the name of
2232 # Stephanie Adams whose job was listed as "Inns North Support Officer for
2233 # Arctic Co-operatives." I was under the impression that Stephanie lived
2234 # and worked in Resolute Bay...
2236 # On March 14/2011 I phoned the hamlet office again. I was told that
2237 # Resolute Bay had been using Central Standard Time over the winter of
2238 # 2010-2011 and that the clocks had therefore been moved one hour ahead
2239 # on March 13/2011. The person I talked to was aware that Resolute Bay
2240 # had previously experimented with Eastern Standard Time but he could not
2241 # tell me when the practice had stopped.
2243 # On March 17/2011 I searched the Web to find an e-mail address of
2244 # somebody that might be able to tell me exactly when Resolute Bay went
2245 # off Eastern Standard Time. I stumbled on the name "Aziz Kheraj." Aziz
2246 # used to be the mayor of Resolute Bay and he apparently owns half the
2247 # businesses including "South Camp Inn." This website has some info on
2249 # http://www.uphere.ca/node/493
2251 # I sent Aziz an e-mail asking when Resolute Bay had stopped using
2252 # Eastern Standard Time.
2254 # Aziz responded quickly with this: "hi, The time was not changed for the
2255 # 1 year only, the following year, the community went back to the old way
2256 # of "spring ahead-fall behind" currently we are zulu plus 5 hrs and in
2257 # the winter Zulu plus 6 hrs"
2259 # This of course conflicted with everything I had ascertained in November 2008.
2261 # I sent Aziz a copy of my 2008 e-mail exchange with Stephanie. Aziz
2262 # responded with this: "Hi, Stephanie lives in Winnipeg. I live here, You
2263 # may want to check with the weather office in Resolute Bay or do a
2264 # search on the weather through Env. Canada. web site"
2266 # If I had realized the Stephanie did not live in Resolute Bay I would
2267 # never have contacted her. I now believe that all the information I
2268 # obtained in November 2008 should be ignored...
2269 # I apologize for reporting incorrect information in 2008.
2271 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
2272 Rule NT_YK 1918 only - Apr 14 2:00 1:00 D
2273 Rule NT_YK 1918 only - Oct 27 2:00 0 S
2274 Rule NT_YK 1919 only - May 25 2:00 1:00 D
2275 Rule NT_YK 1919 only - Nov 1 0:00 0 S
2276 Rule NT_YK 1942 only - Feb 9 2:00 1:00 W # War
2277 Rule NT_YK 1945 only - Aug 14 23:00u 1:00 P # Peace
2278 Rule NT_YK 1945 only - Sep 30 2:00 0 S
2279 Rule NT_YK 1965 only - Apr lastSun 0:00 2:00 DD
2280 Rule NT_YK 1965 only - Oct lastSun 2:00 0 S
2281 Rule NT_YK 1980 1986 - Apr lastSun 2:00 1:00 D
2282 Rule NT_YK 1980 2006 - Oct lastSun 2:00 0 S
2283 Rule NT_YK 1987 2006 - Apr Sun>=1 2:00 1:00 D
2284 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2286 Zone America/Pangnirtung 0 - -00 1921 # trading post est.
2287 -4:00 NT_YK A%sT 1995 Apr Sun>=1 2:00
2288 -5:00 Canada E%sT 1999 Oct 31 2:00
2289 -6:00 Canada C%sT 2000 Oct 29 2:00
2291 # formerly Frobisher Bay
2292 Zone America/Iqaluit 0 - -00 1942 Aug # Frobisher Bay est.
2293 -5:00 NT_YK E%sT 1999 Oct 31 2:00
2294 -6:00 Canada C%sT 2000 Oct 29 2:00
2297 Zone America/Resolute 0 - -00 1947 Aug 31 # Resolute founded
2298 -6:00 NT_YK C%sT 2000 Oct 29 2:00
2299 -5:00 - EST 2001 Apr 1 3:00
2300 -6:00 Canada C%sT 2006 Oct 29 2:00
2301 -5:00 - EST 2007 Mar 11 3:00
2304 Zone America/Rankin_Inlet 0 - -00 1957 # Rankin Inlet founded
2305 -6:00 NT_YK C%sT 2000 Oct 29 2:00
2306 -5:00 - EST 2001 Apr 1 3:00
2308 # aka Iqaluktuuttiaq
2309 Zone America/Cambridge_Bay 0 - -00 1920 # trading post est.?
2310 -7:00 NT_YK M%sT 1999 Oct 31 2:00
2311 -6:00 Canada C%sT 2000 Oct 29 2:00
2312 -5:00 - EST 2000 Nov 5 0:00
2313 -6:00 - CST 2001 Apr 1 3:00
2315 Zone America/Yellowknife 0 - -00 1935 # Yellowknife founded?
2316 -7:00 NT_YK M%sT 1980
2318 Zone America/Inuvik 0 - -00 1953 # Inuvik founded
2319 -8:00 NT_YK P%sT 1979 Apr lastSun 2:00
2320 -7:00 NT_YK M%sT 1980
2322 Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20
2323 -9:00 NT_YK Y%sT 1967 May 28 0:00
2324 -8:00 NT_YK P%sT 1980
2326 Zone America/Dawson -9:17:40 - LMT 1900 Aug 20
2327 -9:00 NT_YK Y%sT 1973 Oct 28 0:00
2328 -8:00 NT_YK P%sT 1980
2332 ###############################################################################
2336 # From Paul Eggert (2014-12-07):
2337 # The Investigation and Analysis Service of the
2338 # Mexican Library of Congress (MLoC) has published a
2339 # history of Mexican local time (in Spanish)
2340 # http://www.diputados.gob.mx/bibliot/publica/inveyana/polisoc/horver/index.htm
2342 # Here are the discrepancies between Shanks & Pottenger (S&P) and the MLoC.
2343 # (In all cases we go with the MLoC.)
2344 # S&P report that Baja was at -8:00 in 1922/1923.
2345 # S&P say the 1930 transition in Baja was 1930-11-16.
2346 # S&P report no DST during summer 1931.
2347 # S&P report a transition at 1932-03-30 23:00, not 1932-04-01.
2349 # From Gwillim Law (2001-02-20):
2350 # There are some other discrepancies between the Decrees page and the
2351 # tz database. I think they can best be explained by supposing that
2352 # the researchers who prepared the Decrees page failed to find some of
2353 # the relevant documents.
2355 # From Alan Perry (1996-02-15):
2356 # A guy from our Mexico subsidiary finally found the Presidential Decree
2357 # outlining the timezone changes in Mexico.
2359 # ------------- Begin Forwarded Message -------------
2361 # I finally got my hands on the Official Presidential Decree that sets up the
2362 # rules for the DST changes. The rules are:
2364 # 1. The country is divided in 3 timezones:
2365 # - Baja California Norte (the Mexico/BajaNorte TZ)
2366 # - Baja California Sur, Nayarit, Sinaloa and Sonora (the Mexico/BajaSur TZ)
2367 # - The rest of the country (the Mexico/General TZ)
2369 # 2. From the first Sunday in April at 2:00 AM to the last Sunday in October
2370 # at 2:00 AM, the times in each zone are as follows:
2375 # 3. The rest of the year, the times are as follows:
2380 # The Decree was published in Mexico's Official Newspaper on January 4th.
2382 # -------------- End Forwarded Message --------------
2383 # From Paul Eggert (1996-06-12):
2384 # For an English translation of the decree, see
2385 # "Diario Oficial: Time Zone Changeover" (1996-01-04).
2386 # http://mexico-travel.com/extra/timezone_eng.html
2388 # From Rives McDow (1998-10-08):
2389 # The State of Quintana Roo has reverted back to central STD and DST times
2390 # (i.e. UTC -0600 and -0500 as of 1998-08-02).
2392 # From Rives McDow (2000-01-10):
2393 # Effective April 4, 1999 at 2:00 AM local time, Sonora changed to the time
2394 # zone 5 hours from the International Date Line, and will not observe daylight
2395 # savings time so as to stay on the same time zone as the southern part of
2396 # Arizona year round.
2398 # From Jesper Nørgaard, translating
2399 # <http://www.reforma.com/nacional/articulo/064327/> (2001-01-17):
2400 # In Oaxaca, the 55.000 teachers from the Section 22 of the National
2401 # Syndicate of Education Workers, refuse to apply daylight saving each
2402 # year, so that the more than 10,000 schools work at normal hour the
2405 # From Gwillim Law (2001-01-19):
2406 # <http://www.reforma.com/negocios_y_dinero/articulo/064481/> ... says
2408 # January 17, 2000 - The Energy Secretary, Ernesto Martens, announced
2409 # that Summer Time will be reduced from seven to five months, starting
2411 # http://www.publico.com.mx/scripts/texto3.asp?action=pagina&pag=21&pos=p&secc=naci&date=01/17/2001
2412 # [translated], says "summer time will ... take effect on the first Sunday
2413 # in May, and end on the last Sunday of September.
2415 # From Arthur David Olson (2001-01-25):
2416 # The 2001-01-24 traditional Washington Post contained the page one
2417 # story "Timely Issue Divides Mexicans."...
2418 # http://www.washingtonpost.com/wp-dyn/articles/A37383-2001Jan23.html
2419 # ... Mexico City Mayor López Obrador "...is threatening to keep
2420 # Mexico City and its 20 million residents on a different time than
2421 # the rest of the country..." In particular, López Obrador would abolish
2422 # observation of Daylight Saving Time.
2424 # Official statute published by the Energy Department
2425 # http://www.conae.gob.mx/ahorro/decretohorver2001.html#decre
2426 # (2001-02-01) shows Baja and Chihauhua as still using US DST rules,
2427 # and Sonora with no DST. This was reported by Jesper Nørgaard (2001-02-03).
2429 # From Paul Eggert (2001-03-03):
2431 # http://www.latimes.com/news/nation/20010303/t000018766.html
2432 # James F. Smith writes in today's LA Times
2433 # * Sonora will continue to observe standard time.
2434 # * Last week Mexico City's mayor Andrés Manuel López Obrador decreed that
2435 # the Federal District will not adopt DST.
2436 # * 4 of 16 district leaders announced they'll ignore the decree.
2437 # * The decree does not affect federal-controlled facilities including
2438 # the airport, banks, hospitals, and schools.
2440 # For now we'll assume that the Federal District will bow to federal rules.
2442 # From Jesper Nørgaard (2001-04-01):
2443 # I found some references to the Mexican application of daylight
2444 # saving, which modifies what I had already sent you, stating earlier
2445 # that a number of northern Mexican states would go on daylight
2446 # saving. The modification reverts this to only cover Baja California
2447 # (Norte), while all other states (except Sonora, who has no daylight
2448 # saving all year) will follow the original decree of president
2449 # Vicente Fox, starting daylight saving May 6, 2001 and ending
2450 # September 30, 2001.
2451 # References: "Diario de Monterrey" <http://www.diariodemonterrey.com/index.asp>
2452 # Palabra <http://palabra.infosel.com/010331/primera/ppri3101.pdf> (2001-03-31)
2454 # From Reuters (2001-09-04):
2455 # Mexico's Supreme Court on Tuesday declared that daylight savings was
2456 # unconstitutional in Mexico City, creating the possibility the
2457 # capital will be in a different time zone from the rest of the nation
2458 # next year.... The Supreme Court's ruling takes effect at 2:00
2459 # a.m. (0800 GMT) on Sept. 30, when Mexico is scheduled to revert to
2460 # standard time. "This is so residents of the Federal District are not
2461 # subject to unexpected time changes," a statement from the court said.
2463 # From Jesper Nørgaard Welen (2002-03-12):
2464 # ... consulting my local grocery store(!) and my coworkers, they all insisted
2465 # that a new decision had been made to reinstate US style DST in Mexico....
2466 # http://www.conae.gob.mx/ahorro/horaver2001_m1_2002.html (2002-02-20)
2467 # confirms this. Sonora as usual is the only state where DST is not applied.
2469 # From Steffen Thorsen (2009-12-28):
2471 # Steffen Thorsen wrote:
2472 # > Mexico's House of Representatives has approved a proposal for northern
2473 # > Mexico's border cities to share the same daylight saving schedule as
2474 # > the United States.
2475 # Now this has passed both the Congress and the Senate, so starting from
2476 # 2010, some border regions will be the same:
2477 # http://www.signonsandiego.com/news/2009/dec/28/clocks-will-match-both-sides-border/
2478 # http://www.elmananarey.com/diario/noticia/nacional/noticias/empatan_horario_de_frontera_con_eu/621939
2481 # Could not find the new law text, but the proposed law text changes are here:
2482 # http://gaceta.diputados.gob.mx/Gaceta/61/2009/dic/20091210-V.pdf
2483 # (Gaceta Parlamentaria)
2485 # There is also a list of the votes here:
2486 # http://gaceta.diputados.gob.mx/Gaceta/61/2009/dic/V2-101209.html
2489 # https://www.timeanddate.com/news/time/north-mexico-dst-change.html
2491 # From Arthur David Olson (2010-01-20):
2493 # http://dof.gob.mx/nota_detalle.php?codigo=5127480&fecha=06/01/2010
2494 # includes this text:
2495 # En los municipios fronterizos de Tijuana y Mexicali en Baja California;
2496 # Juárez y Ojinaga en Chihuahua; Acuña y Piedras Negras en Coahuila;
2497 # Anáhuac en Nuevo León; y Nuevo Laredo, Reynosa y Matamoros en
2498 # Tamaulipas, la aplicación de este horario estacional surtirá efecto
2499 # desde las dos horas del segundo domingo de marzo y concluirá a las dos
2500 # horas del primer domingo de noviembre.
2501 # En los municipios fronterizos que se encuentren ubicados en la franja
2502 # fronteriza norte en el territorio comprendido entre la línea
2503 # internacional y la línea paralela ubicada a una distancia de veinte
2504 # kilómetros, así como la Ciudad de Ensenada, Baja California, hacia el
2505 # interior del país, la aplicación de este horario estacional surtirá
2506 # efecto desde las dos horas del segundo domingo de marzo y concluirá a
2507 # las dos horas del primer domingo de noviembre.
2509 # From Steffen Thorsen (2014-12-08), translated by Gwillim Law:
2510 # The Mexican state of Quintana Roo will likely change to EST in 2015.
2512 # http://www.unioncancun.mx/articulo/2014/12/04/medio-ambiente/congreso-aprueba-una-hora-mas-de-sol-en-qroo
2513 # "With this change, the time conflict that has existed between the municipios
2514 # of Quintana Roo and the municipio of Felipe Carrillo Puerto may come to an
2515 # end. The latter declared itself in rebellion 15 years ago when a time change
2516 # was initiated in Mexico, and since then it has refused to change its time
2517 # zone along with the rest of the country."
2519 # From Steffen Thorsen (2015-01-14), translated by Gwillim Law:
2520 # http://sipse.com/novedades/confirman-aplicacion-de-nueva-zona-horaria-para-quintana-roo-132331.html
2521 # "...the new time zone will come into effect at two o'clock on the first Sunday
2522 # of February, when we will have to advance the clock one hour from its current
2524 # Also, the new zone will not use DST.
2526 # From Carlos Raúl Perasso (2015-02-02):
2527 # The decree that modifies the Mexican Hour System Law has finally
2528 # been published at the Diario Oficial de la Federación
2529 # http://www.dof.gob.mx/nota_detalle.php?codigo=5380123&fecha=31/01/2015
2530 # It establishes 5 zones for Mexico:
2531 # 1- Zona Centro (Central Zone): Corresponds to longitude 90 W,
2532 # includes most of Mexico, excluding what's mentioned below.
2533 # 2- Zona Pacífico (Pacific Zone): Longitude 105 W, includes the
2534 # states of Baja California Sur; Chihuahua; Nayarit (excluding Bahía
2535 # de Banderas which lies in Central Zone); Sinaloa and Sonora.
2536 # 3- Zona Noroeste (Northwest Zone): Longitude 120 W, includes the
2537 # state of Baja California.
2538 # 4- Zona Sureste (Southeast Zone): Longitude 75 W, includes the state
2540 # 5- The islands, reefs and keys shall take their timezone from the
2541 # longitude they are located at.
2543 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
2544 Rule Mexico 1939 only - Feb 5 0:00 1:00 D
2545 Rule Mexico 1939 only - Jun 25 0:00 0 S
2546 Rule Mexico 1940 only - Dec 9 0:00 1:00 D
2547 Rule Mexico 1941 only - Apr 1 0:00 0 S
2548 Rule Mexico 1943 only - Dec 16 0:00 1:00 W # War
2549 Rule Mexico 1944 only - May 1 0:00 0 S
2550 Rule Mexico 1950 only - Feb 12 0:00 1:00 D
2551 Rule Mexico 1950 only - Jul 30 0:00 0 S
2552 Rule Mexico 1996 2000 - Apr Sun>=1 2:00 1:00 D
2553 Rule Mexico 1996 2000 - Oct lastSun 2:00 0 S
2554 Rule Mexico 2001 only - May Sun>=1 2:00 1:00 D
2555 Rule Mexico 2001 only - Sep lastSun 2:00 0 S
2556 Rule Mexico 2002 max - Apr Sun>=1 2:00 1:00 D
2557 Rule Mexico 2002 max - Oct lastSun 2:00 0 S
2558 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2559 # Quintana Roo; represented by Cancún
2560 Zone America/Cancun -5:47:04 - LMT 1922 Jan 1 0:12:56
2561 -6:00 - CST 1981 Dec 23
2562 -5:00 Mexico E%sT 1998 Aug 2 2:00
2563 -6:00 Mexico C%sT 2015 Feb 1 2:00
2565 # Campeche, Yucatán; represented by Mérida
2566 Zone America/Merida -5:58:28 - LMT 1922 Jan 1 0:01:32
2567 -6:00 - CST 1981 Dec 23
2568 -5:00 - EST 1982 Dec 2
2570 # Coahuila, Nuevo León, Tamaulipas (near US border)
2571 # This includes the following municipalities:
2572 # in Coahuila: Ocampo, Acuña, Zaragoza, Jiménez, Piedras Negras, Nava,
2573 # Guerrero, Hidalgo.
2574 # in Nuevo León: Anáhuac, Los Aldama.
2575 # in Tamaulipas: Nuevo Laredo, Guerrero, Mier, Miguel Alemán, Camargo,
2576 # Gustavo Díaz Ordaz, Reynosa, Río Bravo, Valle Hermoso, Matamoros.
2577 # See: Inicia mañana Horario de Verano en zona fronteriza, El Universal,
2579 # http://www.eluniversal.com.mx/articulo/estados/2016/03/12/inicia-manana-horario-de-verano-en-zona-fronteriza
2580 Zone America/Matamoros -6:40:00 - LMT 1921 Dec 31 23:20:00
2583 -6:00 Mexico C%sT 2010
2585 # Durango; Coahuila, Nuevo León, Tamaulipas (away from US border)
2586 Zone America/Monterrey -6:41:16 - LMT 1921 Dec 31 23:18:44
2591 Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 0:23:24
2592 -7:00 - MST 1927 Jun 10 23:00
2593 -6:00 - CST 1930 Nov 15
2594 -7:00 - MST 1931 May 1 23:00
2595 -6:00 - CST 1931 Oct
2596 -7:00 - MST 1932 Apr 1
2597 -6:00 Mexico C%sT 2001 Sep 30 2:00
2598 -6:00 - CST 2002 Feb 20
2600 # Chihuahua (near US border)
2601 # This includes the municipalities of Janos, Ascensión, Juárez, Guadalupe,
2602 # Práxedis G Guerrero, Coyame del Sotol, Ojinaga, and Manuel Benavides.
2603 # (See the 2016-03-12 El Universal source mentioned above.)
2604 Zone America/Ojinaga -6:57:40 - LMT 1922 Jan 1 0:02:20
2605 -7:00 - MST 1927 Jun 10 23:00
2606 -6:00 - CST 1930 Nov 15
2607 -7:00 - MST 1931 May 1 23:00
2608 -6:00 - CST 1931 Oct
2609 -7:00 - MST 1932 Apr 1
2611 -6:00 Mexico C%sT 1998
2612 -6:00 - CST 1998 Apr Sun>=1 3:00
2613 -7:00 Mexico M%sT 2010
2615 # Chihuahua (away from US border)
2616 Zone America/Chihuahua -7:04:20 - LMT 1921 Dec 31 23:55:40
2617 -7:00 - MST 1927 Jun 10 23:00
2618 -6:00 - CST 1930 Nov 15
2619 -7:00 - MST 1931 May 1 23:00
2620 -6:00 - CST 1931 Oct
2621 -7:00 - MST 1932 Apr 1
2623 -6:00 Mexico C%sT 1998
2624 -6:00 - CST 1998 Apr Sun>=1 3:00
2627 Zone America/Hermosillo -7:23:52 - LMT 1921 Dec 31 23:36:08
2628 -7:00 - MST 1927 Jun 10 23:00
2629 -6:00 - CST 1930 Nov 15
2630 -7:00 - MST 1931 May 1 23:00
2631 -6:00 - CST 1931 Oct
2632 -7:00 - MST 1932 Apr 1
2633 -6:00 - CST 1942 Apr 24
2634 -7:00 - MST 1949 Jan 14
2636 -7:00 Mexico M%sT 1999
2639 # From Alexander Krivenyshev (2010-04-21):
2640 # According to news, Bahía de Banderas (Mexican state of Nayarit)
2641 # changed time zone UTC-7 to new time zone UTC-6 on April 4, 2010 (to
2642 # share the same time zone as nearby city Puerto Vallarta, Jalisco).
2645 # Bahía de Banderas homologa su horario al del centro del
2646 # país, a partir de este domingo
2647 # http://www.nayarit.gob.mx/notes.asp?id=20748
2649 # Bahía de Banderas homologa su horario con el del Centro del
2651 # http://www.bahiadebanderas.gob.mx/principal/index.php?option=com_content&view=article&id=261:bahia-de-banderas-homologa-su-horario-con-el-del-centro-del-pais&catid=42:comunicacion-social&Itemid=50
2654 # Puerto Vallarta and Bahía de Banderas: One Time Zone
2655 # http://virtualvallarta.com/puertovallarta/puertovallarta/localnews/2009-12-03-Puerto-Vallarta-and-Bahia-de-Banderas-One-Time-Zone.shtml
2656 # http://www.worldtimezone.com/dst_news/dst_news_mexico08.html
2658 # "Mexico's Senate approved the amendments to the Mexican Schedule System that
2659 # will allow Bahía de Banderas and Puerto Vallarta to share the same time
2661 # Baja California Sur, Nayarit, Sinaloa
2663 # From Arthur David Olson (2010-05-01):
2664 # Use "Bahia_Banderas" to keep the name to fourteen characters.
2667 Zone America/Mazatlan -7:05:40 - LMT 1921 Dec 31 23:54:20
2668 -7:00 - MST 1927 Jun 10 23:00
2669 -6:00 - CST 1930 Nov 15
2670 -7:00 - MST 1931 May 1 23:00
2671 -6:00 - CST 1931 Oct
2672 -7:00 - MST 1932 Apr 1
2673 -6:00 - CST 1942 Apr 24
2674 -7:00 - MST 1949 Jan 14
2679 Zone America/Bahia_Banderas -7:01:00 - LMT 1921 Dec 31 23:59:00
2680 -7:00 - MST 1927 Jun 10 23:00
2681 -6:00 - CST 1930 Nov 15
2682 -7:00 - MST 1931 May 1 23:00
2683 -6:00 - CST 1931 Oct
2684 -7:00 - MST 1932 Apr 1
2685 -6:00 - CST 1942 Apr 24
2686 -7:00 - MST 1949 Jan 14
2688 -7:00 Mexico M%sT 2010 Apr 4 2:00
2692 Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 0:11:56
2694 -8:00 - PST 1927 Jun 10 23:00
2695 -7:00 - MST 1930 Nov 15
2696 -8:00 - PST 1931 Apr 1
2697 -8:00 1:00 PDT 1931 Sep 30
2698 -8:00 - PST 1942 Apr 24
2699 -8:00 1:00 PWT 1945 Aug 14 23:00u
2700 -8:00 1:00 PPT 1945 Nov 12 # Peace
2701 -8:00 - PST 1948 Apr 5
2702 -8:00 1:00 PDT 1949 Jan 14
2707 -8:00 Mexico P%sT 2001
2708 -8:00 US P%sT 2002 Feb 20
2709 -8:00 Mexico P%sT 2010
2711 # From Paul Eggert (2006-03-22):
2712 # Formerly there was an America/Ensenada zone, which differed from
2713 # America/Tijuana only in that it did not observe DST from 1976
2714 # through 1995. This was as per Shanks (1999). But Shanks & Pottenger say
2715 # Ensenada did not observe DST from 1948 through 1975. Guy Harris reports
2716 # that the 1987 OAG says "Only Ensenada, Mexicali, San Felipe and
2717 # Tijuana observe DST," which agrees with Shanks & Pottenger but implies that
2718 # DST-observance was a town-by-town matter back then. This concerns
2719 # data after 1970 so most likely there should be at least one Zone
2720 # other than America/Tijuana for Baja, but it's not clear yet what its
2721 # name or contents should be.
2723 # From Paul Eggert (2015-10-08):
2724 # Formerly there was an America/Santa_Isabel zone, but this appears to
2725 # have come from a misreading of
2726 # http://dof.gob.mx/nota_detalle.php?codigo=5127480&fecha=06/01/2010
2727 # It has been moved to the 'backward' file.
2733 ###############################################################################
2736 # Antigua and Barbuda
2737 # See America/Port_of_Spain.
2741 # For 1899 Milne gives -5:09:29.5; round that.
2743 # From Sue Williams (2006-12-07):
2744 # The Bahamas announced about a month ago that they plan to change their DST
2745 # rules to sync with the U.S. starting in 2007....
2746 # http://www.jonesbahamas.com/?c=45&a=10412
2748 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
2749 Rule Bahamas 1964 1975 - Oct lastSun 2:00 0 S
2750 Rule Bahamas 1964 1975 - Apr lastSun 2:00 1:00 D
2751 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2752 Zone America/Nassau -5:09:30 - LMT 1912 Mar 2
2753 -5:00 Bahamas E%sT 1976
2758 # For 1899 Milne gives -3:58:29.2; round that.
2760 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
2761 Rule Barb 1977 only - Jun 12 2:00 1:00 D
2762 Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S
2763 Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D
2764 Rule Barb 1979 only - Sep 30 2:00 0 S
2765 Rule Barb 1980 only - Sep 25 2:00 0 S
2766 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2767 Zone America/Barbados -3:58:29 - LMT 1924 # Bridgetown
2768 -3:58:29 - BMT 1932 # Bridgetown Mean Time
2772 # Whitman entirely disagrees with Shanks; go with Shanks & Pottenger.
2773 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
2774 Rule Belize 1918 1942 - Oct Sun>=2 0:00 0:30 -0530
2775 Rule Belize 1919 1943 - Feb Sun>=9 0:00 0 CST
2776 Rule Belize 1973 only - Dec 5 0:00 1:00 CDT
2777 Rule Belize 1974 only - Feb 9 0:00 0 CST
2778 Rule Belize 1982 only - Dec 18 0:00 1:00 CDT
2779 Rule Belize 1983 only - Feb 12 0:00 0 CST
2780 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2781 Zone America/Belize -5:52:48 - LMT 1912 Apr
2786 # For 1899 Milne gives -4:19:18.3 as the meridian of the clock tower,
2787 # Bermuda dockyard, Ireland I; round that.
2789 # From Dan Jones, reporting in The Royal Gazette (2006-06-26):
2791 # Next year, however, clocks in the US will go forward on the second Sunday
2792 # in March, until the first Sunday in November. And, after the Time Zone
2793 # (Seasonal Variation) Bill 2006 was passed in the House of Assembly on
2794 # Friday, the same thing will happen in Bermuda.
2795 # http://www.theroyalgazette.com/apps/pbcs.dll/article?AID=/20060529/NEWS/105290135
2797 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2798 Zone Atlantic/Bermuda -4:19:18 - LMT 1930 Jan 1 2:00 # Hamilton
2799 -4:00 - AST 1974 Apr 28 2:00
2800 -4:00 Canada A%sT 1976
2804 # See America/Panama.
2808 # Milne gives -5:36:13.3 as San José mean time; round to nearest.
2810 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
2811 Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D
2812 Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S
2813 Rule CR 1991 1992 - Jan Sat>=15 0:00 1:00 D
2814 # IATA SSIM (1991-09) says the following was at 1:00;
2815 # go with Shanks & Pottenger.
2816 Rule CR 1991 only - Jul 1 0:00 0 S
2817 Rule CR 1992 only - Mar 15 0:00 0 S
2818 # There are too many San Josés elsewhere, so we'll use 'Costa Rica'.
2819 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2820 Zone America/Costa_Rica -5:36:13 - LMT 1890 # San José
2821 -5:36:13 - SJMT 1921 Jan 15 # San José Mean Time
2824 # no information; probably like America/Costa_Rica
2828 # From Paul Eggert (2013-02-21):
2829 # Milne gives -5:28:50.45 for the observatory at Havana, -5:29:23.57
2830 # for the port, and -5:30 for meteorological observations.
2831 # For now, stick with Shanks & Pottenger.
2833 # From Arthur David Olson (1999-03-29):
2834 # The 1999-03-28 exhibition baseball game held in Havana, Cuba, between
2835 # the Cuban National Team and the Baltimore Orioles was carried live on
2836 # the Orioles Radio Network, including affiliate WTOP in Washington, DC.
2837 # During the game, play-by-play announcer Jim Hunter noted that
2838 # "We'll be losing two hours of sleep...Cuba switched to Daylight Saving
2839 # Time today." (The "two hour" remark referred to losing one hour of
2840 # sleep on 1999-03-28 - when the announcers were in Cuba as it switched
2841 # to DST - and one more hour on 1999-04-04 - when the announcers will have
2842 # returned to Baltimore, which switches on that date.)
2844 # From Steffen Thorsen (2013-11-11):
2845 # DST start in Cuba in 2004 ... does not follow the same rules as the
2846 # years before. The correct date should be Sunday 2004-03-28 00:00 ...
2847 # https://web.archive.org/web/20040402060750/http://www.granma.cu/espanol/2004/marzo/sab27/reloj.html
2849 # From Evert van der Veer via Steffen Thorsen (2004-10-28):
2850 # Cuba is not going back to standard time this year.
2851 # From Paul Eggert (2006-03-22):
2852 # http://www.granma.cu/ingles/2004/septiembre/juev30/41medid-i.html
2853 # says that it's due to a problem at the Antonio Guiteras
2854 # thermoelectric plant, and says "This October there will be no return
2855 # to normal hours (after daylight saving time)".
2856 # For now, let's assume that it's a temporary measure.
2858 # From Carlos A. Carnero Delgado (2005-11-12):
2859 # This year (just like in 2004-2005) there's no change in time zone
2860 # adjustment in Cuba. We will stay in daylight saving time:
2861 # http://www.granma.cu/espanol/2005/noviembre/mier9/horario.html
2863 # From Jesper Nørgaard Welen (2006-10-21):
2864 # An article in GRANMA INTERNACIONAL claims that Cuba will end
2865 # the 3 years of permanent DST next weekend, see
2866 # http://www.granma.cu/ingles/2006/octubre/lun16/43horario.html
2867 # "On Saturday night, October 28 going into Sunday, October 29, at 01:00,
2868 # watches should be set back one hour - going back to 00:00 hours - returning
2869 # to the normal schedule....
2871 # From Paul Eggert (2007-03-02):
2872 # <http://www.granma.cubaweb.cu/english/news/art89.html>, dated yesterday,
2873 # says Cuban clocks will advance at midnight on March 10.
2874 # For lack of better information, assume Cuba will use US rules,
2875 # except that it switches at midnight standard time as usual.
2877 # From Steffen Thorsen (2007-10-25):
2878 # Carlos Alberto Fonseca Arauz informed me that Cuba will end DST one week
2879 # earlier - on the last Sunday of October, just like in 2006.
2881 # He supplied these references:
2883 # http://www.prensalatina.com.mx/article.asp?ID=%7B4CC32C1B-A9F7-42FB-8A07-8631AFC923AF%7D&language=ES
2884 # http://actualidad.terra.es/sociedad/articulo/cuba_llama_ahorrar_energia_cambio_1957044.htm
2886 # From Alex Krivenyshev (2007-10-25):
2887 # Here is also article from Granma (Cuba):
2889 # Regirá el Horario Normal desde el próximo domingo 28 de octubre
2890 # http://www.granma.cubaweb.cu/2007/10/24/nacional/artic07.html
2892 # http://www.worldtimezone.com/dst_news/dst_news_cuba03.html
2894 # From Arthur David Olson (2008-03-09):
2895 # I'm in Maryland which is now observing United States Eastern Daylight
2896 # Time. At 9:44 local time I used RealPlayer to listen to
2897 # http://media.enet.cu/radioreloj
2898 # a Cuban information station, and heard
2899 # the time announced as "ocho cuarenta y cuatro" ("eight forty-four"),
2900 # indicating that Cuba is still on standard time.
2902 # From Steffen Thorsen (2008-03-12):
2903 # It seems that Cuba will start DST on Sunday, 2007-03-16...
2904 # It was announced yesterday, according to this source (in Spanish):
2905 # http://www.nnc.cubaweb.cu/marzo-2008/cien-1-11-3-08.htm
2907 # Some more background information is posted here:
2908 # https://www.timeanddate.com/news/time/cuba-starts-dst-march-16.html
2910 # The article also says that Cuba has been observing DST since 1963,
2911 # while Shanks (and tzdata) has 1965 as the first date (except in the
2912 # 1940's). Many other web pages in Cuba also claim that it has been
2913 # observed since 1963, but with the exception of 1970 - an exception
2914 # which is not present in tzdata/Shanks. So there is a chance we need to
2915 # change some historic records as well.
2918 # http://www.radiohc.cu/espanol/noticias/mar07/11mar/hor.htm
2920 # From Jesper Nørgaard Welen (2008-03-13):
2921 # The Cuban time change has just been confirmed on the most authoritative
2922 # web site, the Granma. Please check out
2923 # http://www.granma.cubaweb.cu/2008/03/13/nacional/artic10.html
2925 # Basically as expected after Steffen Thorsen's information, the change
2926 # will take place midnight between Saturday and Sunday.
2928 # From Arthur David Olson (2008-03-12):
2929 # Assume Sun>=15 (third Sunday) going forward.
2931 # From Alexander Krivenyshev (2009-03-04)
2932 # According to the Radio Reloj - Cuba will start Daylight Saving Time on
2933 # midnight between Saturday, March 07, 2009 and Sunday, March 08, 2009-
2934 # not on midnight March 14 / March 15 as previously thought.
2936 # http://www.worldtimezone.com/dst_news/dst_news_cuba05.html
2939 # From Arthur David Olson (2009-03-09)
2940 # I listened over the Internet to
2941 # http://media.enet.cu/readioreloj
2942 # this morning; when it was 10:05 a. m. here in Bethesda, Maryland the
2943 # the time was announced as "diez cinco" - the same time as here, indicating
2944 # that has indeed switched to DST. Assume second Sunday from 2009 forward.
2946 # From Steffen Thorsen (2011-03-08):
2947 # Granma announced that Cuba is going to start DST on 2011-03-20 00:00:00
2948 # this year. Nothing about the end date known so far (if that has
2952 # http://granma.co.cu/2011/03/08/nacional/artic01.html
2955 # https://www.timeanddate.com/news/time/cuba-starts-dst-2011.html
2957 # From Steffen Thorsen (2011-10-30)
2958 # Cuba will end DST two weeks later this year. Instead of going back
2959 # tonight, it has been delayed to 2011-11-13 at 01:00.
2961 # One source (Spanish)
2962 # http://www.radioangulo.cu/noticias/cuba/17105-cuba-restablecera-el-horario-del-meridiano-de-greenwich.html
2965 # https://www.timeanddate.com/news/time/cuba-time-changes-2011.html
2967 # From Steffen Thorsen (2012-03-01)
2968 # According to Radio Reloj, Cuba will start DST on Midnight between March
2971 # Radio Reloj has the following info (Spanish):
2972 # http://www.radioreloj.cu/index.php/noticias-radio-reloj/71-miscelaneas/7529-cuba-aplicara-el-horario-de-verano-desde-el-1-de-abril
2975 # https://www.timeanddate.com/news/time/cuba-starts-dst-2012.html
2977 # From Steffen Thorsen (2012-11-03):
2978 # Radio Reloj and many other sources report that Cuba is changing back
2979 # to standard time on 2012-11-04:
2980 # http://www.radioreloj.cu/index.php/noticias-radio-reloj/36-nacionales/9961-regira-horario-normal-en-cuba-desde-el-domingo-cuatro-de-noviembre
2981 # From Paul Eggert (2012-11-03):
2982 # For now, assume the future rule is first Sunday in November.
2984 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
2985 Rule Cuba 1928 only - Jun 10 0:00 1:00 D
2986 Rule Cuba 1928 only - Oct 10 0:00 0 S
2987 Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D
2988 Rule Cuba 1940 1942 - Sep Sun>=1 0:00 0 S
2989 Rule Cuba 1945 1946 - Jun Sun>=1 0:00 1:00 D
2990 Rule Cuba 1945 1946 - Sep Sun>=1 0:00 0 S
2991 Rule Cuba 1965 only - Jun 1 0:00 1:00 D
2992 Rule Cuba 1965 only - Sep 30 0:00 0 S
2993 Rule Cuba 1966 only - May 29 0:00 1:00 D
2994 Rule Cuba 1966 only - Oct 2 0:00 0 S
2995 Rule Cuba 1967 only - Apr 8 0:00 1:00 D
2996 Rule Cuba 1967 1968 - Sep Sun>=8 0:00 0 S
2997 Rule Cuba 1968 only - Apr 14 0:00 1:00 D
2998 Rule Cuba 1969 1977 - Apr lastSun 0:00 1:00 D
2999 Rule Cuba 1969 1971 - Oct lastSun 0:00 0 S
3000 Rule Cuba 1972 1974 - Oct 8 0:00 0 S
3001 Rule Cuba 1975 1977 - Oct lastSun 0:00 0 S
3002 Rule Cuba 1978 only - May 7 0:00 1:00 D
3003 Rule Cuba 1978 1990 - Oct Sun>=8 0:00 0 S
3004 Rule Cuba 1979 1980 - Mar Sun>=15 0:00 1:00 D
3005 Rule Cuba 1981 1985 - May Sun>=5 0:00 1:00 D
3006 Rule Cuba 1986 1989 - Mar Sun>=14 0:00 1:00 D
3007 Rule Cuba 1990 1997 - Apr Sun>=1 0:00 1:00 D
3008 Rule Cuba 1991 1995 - Oct Sun>=8 0:00s 0 S
3009 Rule Cuba 1996 only - Oct 6 0:00s 0 S
3010 Rule Cuba 1997 only - Oct 12 0:00s 0 S
3011 Rule Cuba 1998 1999 - Mar lastSun 0:00s 1:00 D
3012 Rule Cuba 1998 2003 - Oct lastSun 0:00s 0 S
3013 Rule Cuba 2000 2003 - Apr Sun>=1 0:00s 1:00 D
3014 Rule Cuba 2004 only - Mar lastSun 0:00s 1:00 D
3015 Rule Cuba 2006 2010 - Oct lastSun 0:00s 0 S
3016 Rule Cuba 2007 only - Mar Sun>=8 0:00s 1:00 D
3017 Rule Cuba 2008 only - Mar Sun>=15 0:00s 1:00 D
3018 Rule Cuba 2009 2010 - Mar Sun>=8 0:00s 1:00 D
3019 Rule Cuba 2011 only - Mar Sun>=15 0:00s 1:00 D
3020 Rule Cuba 2011 only - Nov 13 0:00s 0 S
3021 Rule Cuba 2012 only - Apr 1 0:00s 1:00 D
3022 Rule Cuba 2012 max - Nov Sun>=1 0:00s 0 S
3023 Rule Cuba 2013 max - Mar Sun>=8 0:00s 1:00 D
3025 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3026 Zone America/Havana -5:29:28 - LMT 1890
3027 -5:29:36 - HMT 1925 Jul 19 12:00 # Havana MT
3031 # See America/Port_of_Spain.
3033 # Dominican Republic
3035 # From Steffen Thorsen (2000-10-30):
3036 # Enrique Morales reported to me that the Dominican Republic has changed the
3037 # time zone to Eastern Standard Time as of Sunday 29 at 2 am....
3038 # http://www.listin.com.do/antes/261000/republica/princi.html
3040 # From Paul Eggert (2000-12-04):
3041 # That URL (2000-10-26, in Spanish) says they planned to use US-style DST.
3043 # From Rives McDow (2000-12-01):
3044 # Dominican Republic changed its mind and presidential decree on Tuesday,
3045 # November 28, 2000, with a new decree. On Sunday, December 3 at 1:00 AM the
3046 # Dominican Republic will be reverting to 8 hours from the International Date
3047 # Line, and will not be using DST in the foreseeable future. The reason they
3048 # decided to use DST was to be in synch with Puerto Rico, who was also going
3049 # to implement DST. When Puerto Rico didn't implement DST, the president
3050 # decided to revert.
3053 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
3054 Rule DR 1966 only - Oct 30 0:00 1:00 EDT
3055 Rule DR 1967 only - Feb 28 0:00 0 EST
3056 Rule DR 1969 1973 - Oct lastSun 0:00 0:30 -0430
3057 Rule DR 1970 only - Feb 21 0:00 0 EST
3058 Rule DR 1971 only - Jan 20 0:00 0 EST
3059 Rule DR 1972 1974 - Jan 21 0:00 0 EST
3060 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3061 Zone America/Santo_Domingo -4:39:36 - LMT 1890
3062 -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT
3063 -5:00 DR %s 1974 Oct 27
3064 -4:00 - AST 2000 Oct 29 2:00
3065 -5:00 US E%sT 2000 Dec 3 1:00
3070 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
3071 Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D
3072 Rule Salv 1987 1988 - Sep lastSun 0:00 0 S
3073 # There are too many San Salvadors elsewhere, so use America/El_Salvador
3074 # instead of America/San_Salvador.
3075 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3076 Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador
3082 # St Martin (French part)
3083 # See America/Port_of_Spain.
3087 # From Gwillim Law (2006-04-22), after a heads-up from Oscar van Vlijmen:
3088 # Diario Co Latino, at
3089 # <http://www.diariocolatino.com/internacionales/detalles.asp?NewsID=8079>,
3090 # says in an article dated 2006-04-19 that the Guatemalan government had
3091 # decided on that date to advance official time by 60 minutes, to lessen the
3092 # impact of the elevated cost of oil.... Daylight saving time will last from
3093 # 2006-04-29 24:00 (Guatemalan standard time) to 2006-09-30 (time unspecified).
3094 # From Paul Eggert (2006-06-22):
3095 # The Ministry of Energy and Mines, press release CP-15/2006
3096 # (2006-04-19), says DST ends at 24:00. See
3097 # http://www.sieca.org.gt/Sitio_publico/Energeticos/Doc/Medidas/Cambio_Horario_Nac_190406.pdf
3099 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
3100 Rule Guat 1973 only - Nov 25 0:00 1:00 D
3101 Rule Guat 1974 only - Feb 24 0:00 0 S
3102 Rule Guat 1983 only - May 21 0:00 1:00 D
3103 Rule Guat 1983 only - Sep 22 0:00 0 S
3104 Rule Guat 1991 only - Mar 23 0:00 1:00 D
3105 Rule Guat 1991 only - Sep 7 0:00 0 S
3106 Rule Guat 2006 only - Apr 30 0:00 1:00 D
3107 Rule Guat 2006 only - Oct 1 0:00 0 S
3108 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3109 Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5
3113 # From Gwillim Law (2005-04-15):
3114 # Risto O. Nykänen wrote me that Haiti is now on DST.
3115 # I searched for confirmation, and I found a press release
3116 # on the Web page of the Haitian Consulate in Chicago (2005-03-31),
3117 # <http://www.haitianconsulate.org/time.doc>. Translated from French, it says:
3119 # "The Prime Minister's Communication Office notifies the public in general
3120 # and the press in particular that, following a decision of the Interior
3121 # Ministry and the Territorial Collectivities [I suppose that means the
3122 # provinces], Haiti will move to Eastern Daylight Time in the night from next
3123 # Saturday the 2nd to Sunday the 3rd.
3125 # "Consequently, the Prime Minister's Communication Office wishes to inform
3126 # the population that the country's clocks will be set forward one hour
3127 # starting at midnight. This provision will hold until the last Saturday in
3130 # "Port-au-Prince, March 31, 2005"
3132 # From Steffen Thorsen (2006-04-04):
3133 # I have been informed by users that Haiti observes DST this year like
3134 # last year, so the current "only" rule for 2005 might be changed to a
3135 # "max" rule or to last until 2006. (Who knows if they will observe DST
3136 # next year or if they will extend their DST like US/Canada next year).
3138 # I have found this article about it (in French):
3139 # http://www.haitipressnetwork.com/news.cfm?articleID=7612
3141 # The reason seems to be an energy crisis.
3143 # From Stephen Colebourne (2007-02-22):
3144 # Some IATA info: Haiti won't be having DST in 2007.
3146 # From Steffen Thorsen (2012-03-11):
3147 # According to several news sources, Haiti will observe DST this year,
3148 # apparently using the same start and end date as USA/Canada.
3149 # So this means they have already changed their time.
3151 # http://www.alterpresse.org/spip.php?article12510
3152 # http://radiovision2000haiti.net/home/?p=13253
3154 # From Arthur David Olson (2012-03-11):
3155 # The alterpresse.org source seems to show a US-style leap from 2:00 a.m. to
3156 # 3:00 a.m. rather than the traditional Haitian jump at midnight.
3157 # Assume a US-style fall back as well.
3159 # From Steffen Thorsen (2013-03-10):
3160 # It appears that Haiti is observing DST this year as well, same rules
3161 # as US/Canada. They did it last year as well, and it looks like they
3162 # are going to observe DST every year now...
3164 # http://radiovision2000haiti.net/public/haiti-avis-changement-dheure-dimanche/
3165 # http://www.canalplushaiti.net/?p=6714
3167 # From Steffen Thorsen (2016-03-12):
3168 # Jean Antoine, editor of www.haiti-reference.com informed us that Haiti
3169 # are not going on DST this year. Several other resources confirm this: ...
3170 # https://www.radiotelevisioncaraibes.com/presse/heure_d_t_pas_de_changement_d_heure_pr_vu_pour_cet_ann_e.html
3171 # https://www.vantbefinfo.com/changement-dheure-pas-pour-haiti/
3172 # http://news.anmwe.com/haiti-lheure-nationale-ne-sera-ni-avancee-ni-reculee-cette-annee/
3174 # From Steffen Thorsen (2017-03-12):
3175 # We have received 4 mails from different people telling that Haiti
3176 # has started DST again today, and this source seems to confirm that,
3177 # I have not been able to find a more authoritative source:
3178 # https://www.haitilibre.com/en/news-20319-haiti-notices-time-change-in-haiti.html
3180 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
3181 Rule Haiti 1983 only - May 8 0:00 1:00 D
3182 Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D
3183 Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S
3184 # Shanks & Pottenger say AT is 2:00, but IATA SSIM (1991/1997) says 1:00s.
3186 Rule Haiti 1988 1997 - Apr Sun>=1 1:00s 1:00 D
3187 Rule Haiti 1988 1997 - Oct lastSun 1:00s 0 S
3188 Rule Haiti 2005 2006 - Apr Sun>=1 0:00 1:00 D
3189 Rule Haiti 2005 2006 - Oct lastSun 0:00 0 S
3190 Rule Haiti 2012 2015 - Mar Sun>=8 2:00 1:00 D
3191 Rule Haiti 2012 2015 - Nov Sun>=1 2:00 0 S
3192 Rule Haiti 2017 max - Mar Sun>=8 2:00 1:00 D
3193 Rule Haiti 2017 max - Nov Sun>=1 2:00 0 S
3194 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3195 Zone America/Port-au-Prince -4:49:20 - LMT 1890
3196 -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT
3200 # Shanks & Pottenger say 1921 Jan 1; go with Whitman's more precise Apr 1.
3202 # From Paul Eggert (2006-05-05):
3203 # worldtimezone.com reports a 2006-05-02 Spanish-language AP article
3204 # saying Honduras will start using DST midnight Saturday, effective 4
3205 # months until September. La Tribuna reported today
3206 # <http://www.latribuna.hn/99299.html> that Manuel Zelaya, the president
3207 # of Honduras, refused to back down on this.
3209 # From Jesper Nørgaard Welen (2006-08-08):
3210 # It seems that Honduras has returned from DST to standard time this Monday at
3211 # 00:00 hours (prolonging Sunday to 25 hours duration).
3212 # http://www.worldtimezone.com/dst_news/dst_news_honduras04.html
3214 # From Paul Eggert (2006-08-08):
3215 # Also see Diario El Heraldo, The country returns to standard time (2006-08-08).
3216 # http://www.elheraldo.hn/nota.php?nid=54941&sec=12
3217 # It mentions executive decree 18-2006.
3219 # From Steffen Thorsen (2006-08-17):
3220 # Honduras will observe DST from 2007 to 2009, exact dates are not
3221 # published, I have located this authoritative source:
3222 # http://www.presidencia.gob.hn/noticia.aspx?nId=47
3224 # From Steffen Thorsen (2007-03-30):
3225 # http://www.laprensahn.com/pais_nota.php?id04962=7386
3226 # So it seems that Honduras will not enter DST this year....
3228 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
3229 Rule Hond 1987 1988 - May Sun>=1 0:00 1:00 D
3230 Rule Hond 1987 1988 - Sep lastSun 0:00 0 S
3231 Rule Hond 2006 only - May Sun>=1 0:00 1:00 D
3232 Rule Hond 2006 only - Aug Mon>=1 0:00 0 S
3233 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3234 Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr
3237 # Great Swan I ceded by US to Honduras in 1972
3240 # Shanks & Pottenger give -5:07:12, but Milne records -5:07:10.41 from an
3241 # unspecified official document, and says "This time is used throughout the
3242 # island". Go with Milne. Round to the nearest second as required by zic.
3244 # Shanks & Pottenger give April 28 for the 1974 spring-forward transition, but
3245 # Lance Neita writes that Prime Minister Michael Manley decreed it January 5.
3246 # Assume Neita meant Jan 6 02:00, the same as the US. Neita also writes that
3247 # Manley's supporters associated this act with Manley's nickname "Joshua"
3248 # (recall that in the Bible the sun stood still at Joshua's request),
3249 # and with the Rod of Correction which Manley said he had received from
3250 # Haile Selassie, Emperor of Ethiopia. See:
3251 # Neita L. The politician in all of us. Jamaica Observer 2014-09-20
3252 # http://www.jamaicaobserver.com/columns/The-politician-in-all-of-us_17573647
3254 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3255 Zone America/Jamaica -5:07:11 - LMT 1890 # Kingston
3256 -5:07:11 - KMT 1912 Feb # Kingston Mean Time
3262 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3263 Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France
3264 -4:04:20 - FFMT 1911 May # Fort-de-France MT
3265 -4:00 - AST 1980 Apr 6
3266 -4:00 1:00 ADT 1980 Sep 28
3270 # See America/Port_of_Spain.
3274 # This uses Shanks & Pottenger for times before 2005.
3276 # From Steffen Thorsen (2005-04-12):
3277 # I've got reports from 8 different people that Nicaragua just started
3278 # DST on Sunday 2005-04-10, in order to save energy because of
3279 # expensive petroleum. The exact end date for DST is not yet
3280 # announced, only "September" but some sites also say "mid-September".
3281 # Some background information is available on the President's official site:
3282 # http://www.presidencia.gob.ni/Presidencia/Files_index/Secretaria/Notas%20de%20Prensa/Presidente/2005/ABRIL/Gobierno-de-nicaragua-adelanta-hora-oficial-06abril.htm
3283 # The Decree, no 23-2005 is available here:
3284 # http://www.presidencia.gob.ni/buscador_gaceta/BD/DECRETOS/2005/Decreto%2023-2005%20Se%20adelanta%20en%20una%20hora%20en%20todo%20el%20territorio%20nacional%20apartir%20de%20las%2024horas%20del%2009%20de%20Abril.pdf
3286 # From Paul Eggert (2005-05-01):
3287 # The decree doesn't say anything about daylight saving, but for now let's
3288 # assume that it is daylight saving....
3290 # From Gwillim Law (2005-04-21):
3291 # The Associated Press story on the time change, which can be found at
3292 # http://www.lapalmainteractivo.com/guias/content/gen/ap/America_Latina/AMC_GEN_NICARAGUA_HORA.html
3293 # and elsewhere, says (fifth paragraph, translated from Spanish): "The last
3294 # time that a change of clocks was applied to save energy was in the year 2000
3295 # during the Arnoldo Alemán administration."...
3296 # The northamerica file says that Nicaragua has been on UTC-6 continuously
3297 # since December 1998. I wasn't able to find any details of Nicaraguan time
3298 # changes in 2000. Perhaps a note could be added to the northamerica file, to
3299 # the effect that we have indirect evidence that DST was observed in 2000.
3301 # From Jesper Nørgaard Welen (2005-11-02):
3302 # Nicaragua left DST the 2005-10-02 at 00:00 (local time).
3303 # http://www.presidencia.gob.ni/presidencia/files_index/secretaria/comunicados/2005/septiembre/26septiembre-cambio-hora.htm
3306 # From Jesper Nørgaard Welen (2006-05-05):
3307 # http://www.elnuevodiario.com.ni/2006/05/01/nacionales/18410
3308 # (my informal translation)
3309 # By order of the president of the republic, Enrique Bolaños, Nicaragua
3310 # advanced by sixty minutes their official time, yesterday at 2 in the
3311 # morning, and will stay that way until 30th of September.
3313 # From Jesper Nørgaard Welen (2006-09-30):
3314 # http://www.presidencia.gob.ni/buscador_gaceta/BD/DECRETOS/2006/D-063-2006P-PRN-Cambio-Hora.pdf
3315 # My informal translation runs:
3316 # The natural sun time is restored in all the national territory, in that the
3317 # time is returned one hour at 01:00 am of October 1 of 2006.
3319 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
3320 Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D
3321 Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S
3322 Rule Nic 2005 only - Apr 10 0:00 1:00 D
3323 Rule Nic 2005 only - Oct Sun>=1 0:00 0 S
3324 Rule Nic 2006 only - Apr 30 2:00 1:00 D
3325 Rule Nic 2006 only - Oct Sun>=1 1:00 0 S
3326 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3327 Zone America/Managua -5:45:08 - LMT 1890
3328 -5:45:12 - MMT 1934 Jun 23 # Managua Mean Time?
3329 -6:00 - CST 1973 May
3330 -5:00 - EST 1975 Feb 16
3331 -6:00 Nic C%sT 1992 Jan 1 4:00
3332 -5:00 - EST 1992 Sep 24
3338 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3339 Zone America/Panama -5:18:08 - LMT 1890
3340 -5:19:36 - CMT 1908 Apr 22 # Colón Mean Time
3342 Link America/Panama America/Cayman
3345 # There are too many San Juans elsewhere, so we'll use 'Puerto_Rico'.
3346 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3347 Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan
3348 -4:00 - AST 1942 May 3
3354 # See America/Port_of_Spain.
3356 # St Pierre and Miquelon
3357 # There are too many St Pierres elsewhere, so we'll use 'Miquelon'.
3358 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3359 Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre
3360 -4:00 - AST 1980 May
3362 -3:00 Canada -03/-02
3364 # St Vincent and the Grenadines
3365 # See America/Port_of_Spain.
3369 # From Chris Dunn in
3370 # https://bugs.debian.org/415007
3371 # (2007-03-15): In the Turks & Caicos Islands (America/Grand_Turk) the
3372 # daylight saving dates for time changes have been adjusted to match
3373 # the recent U.S. change of dates.
3375 # From Brian Inglis (2007-04-28):
3376 # http://www.turksandcaicos.tc/calendar/index.htm [2007-04-26]
3377 # there is an entry for Nov 4 "Daylight Savings Time Ends 2007" and three
3378 # rows before that there is an out of date entry for Oct:
3379 # "Eastern Standard Times Begins 2007
3380 # Clocks are set back one hour at 2:00 a.m. local Daylight Saving Time"
3381 # indicating that the normal ET rules are followed.
3383 # From Paul Eggert (2014-08-19):
3384 # The 2014-08-13 Cabinet meeting decided to stay on UT -04 year-round. See:
3385 # http://tcweeklynews.com/daylight-savings-time-to-be-maintained-p5353-127.htm
3386 # Model this as a switch from EST/EDT to AST ...
3387 # From Chris Walton (2014-11-04):
3388 # ... the TCI government appears to have delayed the switch to
3389 # "permanent daylight saving time" by one year....
3390 # http://tcweeklynews.com/time-change-to-go-ahead-this-november-p5437-127.htm
3392 # From the Turks & Caicos Cabinet (2017-07-20), heads-up from Steffen Thorsen:
3393 # ... agreed to the reintroduction in TCI of Daylight Saving Time (DST)
3394 # during the summer months and Standard Time, also known as Local
3395 # Time, during the winter months with effect from April 2018 ...
3396 # https://www.gov.uk/government/news/turks-and-caicos-post-cabinet-meeting-statement--3
3398 # From Paul Eggert (2017-08-26):
3399 # The date of effect of the spring 2018 change appears to be March 11,
3400 # which makes more sense. See: Hamilton D. Time change back
3401 # by March 2018 for TCI. Magnetic Media. 2017-08-25.
3402 # http://magneticmediatv.com/2017/08/time-change-back-by-march-2018-for-tci/
3404 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
3405 Zone America/Grand_Turk -4:44:32 - LMT 1890
3406 -5:07:11 - KMT 1912 Feb # Kingston Mean Time
3408 -5:00 US E%sT 2015 Nov Sun>=1 2:00
3409 -4:00 - AST 2018 Mar 11 3:00
3414 # See America/Port_of_Spain.