1 # @(#)northamerica 7.74
2 # also includes Central America and the Caribbean
4 # This data is by no means authoritative; if you think you know better,
5 # go ahead and edit the file (and please send any changes to
6 # tz@elsie.nci.nih.gov for general use in the future).
8 # From Paul Eggert (1999-03-22):
9 # A reliable and entertaining source about time zones is
10 # Derek Howse, Greenwich time and longitude, Philip Wilson Publishers (1997).
12 ###############################################################################
16 # From Paul Eggert (1999-03-31):
17 # Howse writes (pp 121-125) that time zones were invented by
18 # Professor Charles Ferdinand Dowd (1825-1904),
19 # Principal of Temple Grove Ladies' Seminary (Saratoga Springs, NY).
20 # His pamphlet ``A System of National Time for Railroads'' (1870)
21 # was the result of his proposals at the Convention of Railroad Trunk Lines
22 # in New York City (1869-10). His 1870 proposal was based on Washington, DC,
23 # but in 1872-05 he moved the proposed origin to Greenwich.
24 # His proposal was adopted by the railroads on 1883-11-18 at 12:00,
25 # and the most of the country soon followed suit.
27 # From Paul Eggert (2005-04-16):
28 # That 1883 transition occurred at 12:00 new time, not at 12:00 old time.
29 # See p 46 of David Prerau, Seize the daylight, Thunder's Mouth Press (2005).
31 # From Paul Eggert (1995-12-19):
32 # A good source for time zone historical data in the US is
33 # Thomas G. Shanks, The American Atlas (5th edition),
34 # San Diego: ACS Publications, Inc. (1991).
35 # Make sure you have the errata sheet; the book is somewhat useless without it.
36 # It is the source for most of the pre-1991 US and Puerto Rico entries below.
38 # From Paul Eggert (2001-03-06):
39 # Daylight Saving Time was first suggested as a joke by Benjamin Franklin
40 # in his whimsical essay ``An Economical Project for Diminishing the Cost
41 # of Light'' published in the Journal de Paris (1784-04-26).
42 # Not everyone is happy with the results:
44 # I don't really care how time is reckoned so long as there is some
45 # agreement about it, but I object to being told that I am saving
46 # daylight when my reason tells me that I am doing nothing of the kind.
47 # I even object to the implication that I am wasting something
48 # valuable if I stay in bed after the sun has risen. As an admirer
49 # of moonlight I resent the bossy insistence of those who want to
50 # reduce my time for enjoying it. At the back of the Daylight Saving
51 # scheme I detect the bony, blue-fingered hand of Puritanism, eager
52 # to push people into bed earlier, and get them up earlier, to make
53 # them healthy, wealthy and wise in spite of themselves.
55 # -- Robertson Davies, The diary of Samuel Marchbanks,
56 # Clarke, Irwin (1947), XIX, Sunday
58 # For more about the first ten years of DST in the United States, see
59 # Robert Garland's <a href="http://www.clpgh.org/exhibit/dst.html">
60 # Ten years of daylight saving from the Pittsburgh standpoint
61 # (Carnegie Library of Pittsburgh, 1927)</a>.
63 # Shanks says that DST was called "War Time" in the US in 1918 and 1919.
64 # However, DST was imposed by the Standard Time Act of 1918, which
65 # was the first nationwide legal time standard, and apparently
66 # time was just called "Standard Time" or "Daylight Saving Time".
68 # From Arthur David Olson:
69 # US Daylight Saving Time ended on the last Sunday of *October* in 1974.
70 # See, for example, the front page of the Saturday, 1974-10-26
71 # and Sunday, 1974-10-27 editions of the Washington Post.
73 # From Arthur David Olson:
74 # Before the Uniform Time Act of 1966 took effect in 1967, observance of
75 # Daylight Saving Time in the US was by local option, except during wartime.
77 # From Arthur David Olson (2000-09-25):
78 # Last night I heard part of a rebroadcast of a 1945 Arch Oboler radio drama.
79 # In the introduction, Oboler spoke of "Eastern Peace Time."
80 # An AltaVista search turned up
81 # <a href="http://rowayton.org/rhs/hstaug45.html">:
82 # "When the time is announced over the radio now, it is 'Eastern Peace
83 # Time' instead of the old familiar 'Eastern War Time.' Peace is wonderful."
84 # </a> (August 1945) by way of confirmation.
86 # From Joseph Gallant <notquite@hotmail.com>, citing
87 # George H. Douglas, _The Early Days of Radio Broadcasting_ (1987):
88 # At 7 P.M. (Eastern War Time) [on 1945-08-14], the networks were set
89 # to switch to London for Attlee's address, but the American people
90 # never got to hear his speech live. According to one press account,
91 # CBS' Bob Trout was first to announce the word of Japan's surrender,
92 # but a few seconds later, NBC, ABC and Mutual also flashed the word
93 # of surrender, all of whom interrupting the bells of Big Ben in
94 # London which were to precede Mr. Attlee's speech.
96 # From Paul Eggert (2003-02-09): It was Robert St John, not Bob Trout. From
97 # Myrna Oliver's obituary of St John on page B16 of today's Los Angeles Times:
99 # ... a war-weary U.S. clung to radios, awaiting word of Japan's surrender.
100 # Any announcement from Asia would reach St. John's New York newsroom on a
101 # wire service teletype machine, which had prescribed signals for major news.
102 # Associated Press, for example, would ring five bells before spewing out
103 # typed copy of an important story, and 10 bells for news "of transcendental
106 # On Aug. 14, stalling while talking steadily into the NBC networks' open
107 # microphone, St. John heard five bells and waited only to hear a sixth bell,
108 # before announcing confidently: "Ladies and gentlemen, World War II is over.
109 # The Japanese have agreed to our surrender terms."
111 # He had scored a 20-second scoop on other broadcasters.
113 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
114 Rule US 1918 1919 - Mar lastSun 2:00 1:00 D
115 Rule US 1918 1919 - Oct lastSun 2:00 0 S
116 Rule US 1942 only - Feb 9 2:00 1:00 W # War
117 Rule US 1945 only - Aug 14 23:00u 1:00 P # Peace
118 Rule US 1945 only - Sep 30 2:00 0 S
119 Rule US 1967 max - Oct lastSun 2:00 0 S
120 Rule US 1967 1973 - Apr lastSun 2:00 1:00 D
121 Rule US 1974 only - Jan 6 2:00 1:00 D
122 Rule US 1975 only - Feb 23 2:00 1:00 D
123 Rule US 1976 1986 - Apr lastSun 2:00 1:00 D
124 Rule US 1987 max - Apr Sun>=1 2:00 1:00 D
125 # <a href="http://thomas.loc.gov/cgi-bin/bdquery/z?d106:h.r.00177:">
127 # </a> (introduced 1999-01-06) would change April to March in the above rule.
129 # From Bob Devine (1988-01-28):
130 # ...Alaska (and Hawaii) had the timezone names changed in 1967.
132 # Pacific Standard Time(PST) -same-
133 # Yukon Standard Time(YST) -same-
134 # Central Alaska S.T. (CAT) Alaska-Hawaii St[an]dard Time (AHST)
135 # Nome Standard Time (NT) Bering Standard Time (BST)
137 # ...Alaska's timezone lines were redrawn in 1983 to give only 2 tz.
138 # The YST zone now covers nearly all of the state, AHST just part
139 # of the Aleutian islands. No DST.
141 # From Paul Eggert (1995-12-19):
142 # The tables below use `NST', not `NT', for Nome Standard Time.
143 # I invented `CAWT' for Central Alaska War Time.
145 # From U. S. Naval Observatory (1989-01-19):
146 # USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON
147 # USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30
148 # USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON
149 # USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30
150 # USA MOUNTAIN 7 H BEHIND UTC DENVER
151 # USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30
152 # USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO
153 # USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30
154 # USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST)
155 # USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT)
156 # USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W
157 # USA - " - 9 H BEHIND UTC APR 3 - OCT 30
158 # USA HAWAII 10 H BEHIND UTC
159 # USA BERING 11 H BEHIND UTC SAMOA, MIDWAY
161 # From Arthur David Olson (1989-01-21):
162 # The above dates are for 1988.
163 # Note the "AKST" and "AKDT" abbreviations, the claim that there's
164 # no DST in Samoa, and the claim that there is DST in Alaska and the
167 # From Arthur David Olson (1988-02-13):
168 # Legal standard time zone names, from United States Code (1982 Edition and
169 # Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names
170 # up to 1967-04-01 (when most provisions of the Uniform Time Act of 1966
171 # took effect), as explained in sections 263 and 261:
173 # United States standard eastern time
174 # United States standard mountain time
175 # United States standard central time
176 # United States standard Pacific time
178 # United States standard Alaska time
180 # Next, names from 1967-04-01 until 1983-11-30 (the date for
181 # public law 98-181):
182 # Atlantic standard time
183 # eastern standard time
184 # central standard time
185 # mountain standard time
186 # Pacific standard time
187 # Yukon standard time
188 # Alaska-Hawaii standard time
189 # Bering standard time
190 # And after 1983-11-30:
191 # Atlantic standard time
192 # eastern standard time
193 # central standard time
194 # mountain standard time
195 # Pacific standard time
196 # Alaska standard time
197 # Hawaii-Aleutian standard time
198 # Samoa standard time
199 # The law doesn't give abbreviations.
201 # From Paul Eggert (2000-01-08), following a heads-up from Rives McDow:
202 # Public law 106-564 (2000-12-23) introduced the abbreviation
203 # "Chamorro Standard Time" for time in Guam and the Northern Marianas.
204 # See the file "australasia".
207 # US eastern time, represented by New York
209 # Connecticut, Delaware, District of Columbia, most of Florida,
210 # Georgia, southeast Indiana (Clark, Dearborn, Floyd, Harrison, and
211 # Ohio counties), eastern Kentucky, Maine, Maryland, Massachusetts,
212 # New Hampshire, New Jersey, New York, North Carolina, Ohio,
213 # Pennsylvania, Rhode Island, South Carolina, eastern Tennessee,
214 # Vermont, Virginia, West Virginia
216 # From Dave Cantor (2004-11-02):
217 # Early this summer I had the occasion to visit the Mount Washington
218 # Observatory weather station atop (of course!) Mount Washington [, NH]....
219 # One of the staff members said that the station was on Eastern Standard Time
220 # and didn't change their clocks for Daylight Saving ... so that their
221 # reports will always have times which are 5 hours behind UTC.
223 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
224 Rule NYC 1920 only - Mar lastSun 2:00 1:00 D
225 Rule NYC 1920 only - Oct lastSun 2:00 0 S
226 Rule NYC 1921 1966 - Apr lastSun 2:00 1:00 D
227 Rule NYC 1921 1954 - Sep lastSun 2:00 0 S
228 Rule NYC 1955 1966 - Oct lastSun 2:00 0 S
229 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
230 Zone America/New_York -4:56:02 - LMT 1883 Nov 18 12:03:58
237 # US central time, represented by Chicago
239 # Alabama, Arkansas, Florida panhandle (Bay, Calhoun, Escambia,
240 # Gulf, Holmes, Jackson, Okaloosa, Santa Rosa, Walton, and
241 # Washington counties), Illinois, western Indiana
242 # (Gibson, Jasper, Lake, LaPorte, Newton, Porter, Posey, Spencer,
243 # Vanderburgh, and Warrick counties), Iowa, most of Kansas, western
244 # Kentucky, Louisiana, Minnesota, Mississippi, Missouri, eastern
245 # Nebraska, eastern North Dakota, Oklahoma, eastern South Dakota,
246 # western Tennessee, most of Texas, Wisconsin
248 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
249 Rule Chicago 1920 only - Jun 13 2:00 1:00 D
250 Rule Chicago 1920 1921 - Oct lastSun 2:00 0 S
251 Rule Chicago 1921 only - Mar lastSun 2:00 1:00 D
252 Rule Chicago 1922 1966 - Apr lastSun 2:00 1:00 D
253 Rule Chicago 1922 1954 - Sep lastSun 2:00 0 S
254 Rule Chicago 1955 1966 - Oct lastSun 2:00 0 S
255 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
256 Zone America/Chicago -5:50:36 - LMT 1883 Nov 18 12:09:24
258 -6:00 Chicago C%sT 1936 Mar 1 2:00
259 -5:00 - EST 1936 Nov 15 2:00
260 -6:00 Chicago C%sT 1942
262 -6:00 Chicago C%sT 1967
264 # Oliver County, ND switched from mountain to central time on 1992-10-25.
265 Zone America/North_Dakota/Center -6:45:12 - LMT 1883 Nov 18 12:14:48
266 -7:00 US M%sT 1992 Oct 25 02:00
269 # US mountain time, represented by Denver
271 # Colorado, far western Kansas, Montana, western
272 # Nebraska, Nevada border (Jackpot, Owyhee, and Mountain City),
273 # New Mexico, southwestern North Dakota, far eastern Oregon,
274 # western South Dakota, far western Texas (El Paso County, Hudspeth County,
275 # and Pine Springs and Nickel Creek in Culberson County), Utah, Wyoming
277 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
278 Rule Denver 1920 1921 - Mar lastSun 2:00 1:00 D
279 Rule Denver 1920 only - Oct lastSun 2:00 0 S
280 Rule Denver 1921 only - May 22 2:00 0 S
281 Rule Denver 1965 1966 - Apr lastSun 2:00 1:00 D
282 Rule Denver 1965 1966 - Oct lastSun 2:00 0 S
283 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
284 Zone America/Denver -6:59:56 - LMT 1883 Nov 18 12:00:04
286 -7:00 Denver M%sT 1942
288 -7:00 Denver M%sT 1967
291 # US Pacific time, represented by Los Angeles
293 # California, northern Idaho (Benewah, Bonner, Boundary, Clearwater,
294 # Idaho, Kootenai, Latah, Lewis, Nez Perce, and Shoshone counties),
295 # most of Nevada, most of Oregon, and Washington
297 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
298 Rule CA 1948 only - Mar 14 2:00 1:00 D
299 Rule CA 1949 only - Jan 1 2:00 0 S
300 Rule CA 1950 1966 - Apr lastSun 2:00 1:00 D
301 Rule CA 1950 1961 - Sep lastSun 2:00 0 S
302 Rule CA 1962 1966 - Oct lastSun 2:00 0 S
303 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
304 Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 12:07:02
310 # AK%sT is the modern abbreviation for -9:00 per USNO.
312 # From Paul Eggert (2001-05-30):
313 # Howse writes that Alaska switched from the Julian to the Gregorian calendar,
314 # and from east-of-GMT to west-of-GMT days, when the US bought it from Russia.
315 # This was on 1867-10-18, a Friday; the previous day was 1867-10-06 Julian,
316 # also a Friday. Include only the time zone part of this transition,
317 # ignoring the switch from Julian to Gregorian, since we can't represent
318 # the Julian calendar.
320 # As far as we know, none of the exact locations mentioned below were
321 # permanently inhabited in 1867 by anyone using either calendar.
322 # (Yakutat was colonized by the Russians in 1799, but the settlement
323 # was destroyed in 1805 by a Yakutat-kon war party.) However, there
324 # were nearby inhabitants in some cases and for our purposes perhaps
325 # it's best to simply use the official transition.
327 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
328 Zone America/Juneau 15:02:19 - LMT 1867 Oct 18
329 -8:57:41 - LMT 1900 Aug 20 12:00
333 -8:00 US P%sT 1983 Oct 30 2:00
334 -9:00 US Y%sT 1983 Nov 30
336 Zone America/Yakutat 14:41:05 - LMT 1867 Oct 18
337 -9:18:55 - LMT 1900 Aug 20 12:00
341 -9:00 US Y%sT 1983 Nov 30
343 Zone America/Anchorage 14:00:24 - LMT 1867 Oct 18
344 -9:59:36 - LMT 1900 Aug 20 12:00
346 -10:00 US CAT/CAWT 1946
347 -10:00 - CAT 1967 Apr
349 -10:00 US AH%sT 1983 Oct 30 2:00
350 -9:00 US Y%sT 1983 Nov 30
352 Zone America/Nome 12:58:21 - LMT 1867 Oct 18
353 -11:01:38 - LMT 1900 Aug 20 12:00
356 -11:00 - NST 1967 Apr
358 -11:00 US B%sT 1983 Oct 30 2:00
359 -9:00 US Y%sT 1983 Nov 30
361 Zone America/Adak 12:13:21 - LMT 1867 Oct 18
362 -11:46:38 - LMT 1900 Aug 20 12:00
365 -11:00 - NST 1967 Apr
367 -11:00 US B%sT 1983 Oct 30 2:00
368 -10:00 US AH%sT 1983 Nov 30
370 # The following switches don't quite make our 1970 cutoff.
372 # Shanks writes that part of southwest Alaska (e.g. Aniak)
373 # switched from -11:00 to -10:00 on 1968-09-22 at 02:00,
374 # and another part (e.g. Akiak) made the same switch five weeks later.
376 # From David Flater (2004-11-09):
377 # In e-mail, 2004-11-02, Ray Hudson, historian/liaison to the Unalaska
378 # Historic Preservation Commission, provided this information, which
379 # suggests that Unalaska deviated from statutory time from early 1967
380 # possibly until 1983:
382 # Minutes of the Unalaska City Council Meeting, January 10, 1967:
383 # "Except for St. Paul and Akutan, Unalaska is the only important
384 # location not on Alaska Standard Time. The following resolution was
385 # made by William Robinson and seconded by Henry Swanson: Be it
386 # resolved that the City of Unalaska hereby goes to Alaska Standard
387 # Time as of midnight Friday, January 13, 1967 (1 A.M. Saturday,
388 # January 14, Alaska Standard Time.) This resolution was passed with
389 # three votes for and one against."
393 # From Arthur David Olson:
394 # And then there's Hawaii.
395 # DST was observed for one day in 1933;
396 # standard time was changed by half an hour in 1947;
397 # it's always standard as of 1986.
400 # Shanks says the 1933 experiment lasted for three weeks. Go with Shanks.
402 Zone Pacific/Honolulu -10:31:26 - LMT 1900 Jan 1 12:00
403 -10:30 - HST 1933 Apr 30 2:00
404 -10:30 1:00 HDT 1933 May 21 2:00
405 -10:30 US H%sT 1947 Jun 8 2:00
408 # Now we turn to US areas that have diverged from the consensus since 1970.
410 # Arizona mostly uses MST.
412 # From Paul Eggert (2002-10-20):
414 # The information in the rest of this paragraph is derived from the
415 # <a href="http://www.dlapr.lib.az.us/links/daylight.htm">
416 # Daylight Saving Time web page (2002-01-23)</a> maintained by the
417 # Arizona State Library, Archives and Public Records.
418 # Between 1944-01-01 and 1944-04-01 the State of Arizona used standard
419 # time, but by federal law railroads, airlines, bus lines, military
420 # personnel, and some engaged in interstate commerce continued to
421 # observe war (i.e., daylight saving) time. The 1944-03-17 Phoenix
422 # Gazette says that was the date the law changed, and that 04-01 was
423 # the date the state's clocks would change. In 1945 the State of
424 # Arizona used standard time all year, again with exceptions only as
425 # mandated by federal law. Arizona observed DST in 1967, but Arizona
426 # Laws 1968, ch. 183 (effective 1968-03-21) repealed DST.
428 # Shanks says the 1944 experiment came to an end on 1944-03-17.
429 # Go with the Arizona State Library instead.
431 Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 11:31:42
432 -7:00 US M%sT 1944 Jan 1 00:01
433 -7:00 - MST 1944 Apr 1 00:01
434 -7:00 US M%sT 1944 Oct 1 00:01
436 -7:00 US M%sT 1968 Mar 21
438 # From Arthur David Olson (1988-02-13):
439 # A writer from the Inter Tribal Council of Arizona, Inc.,
440 # notes in private correspondence dated 1987-12-28 that "Presently, only the
441 # Navajo Nation participates in the Daylight Saving Time policy, due to its
442 # large size and location in three states." (The "only" means that other
443 # tribal nations don't use DST.)
445 Link America/Denver America/Shiprock
447 # Southern Idaho (Ada, Adams, Bannock, Bear Lake, Bingham, Blaine,
448 # Boise, Bonneville, Butte, Camas, Canyon, Caribou, Cassia, Clark,
449 # Custer, Elmore, Franklin, Fremont, Gem, Gooding, Jefferson, Jerome,
450 # Lemhi, Lincoln, Madison, Minidoka, Oneida, Owyhee, Payette, Power,
451 # Teton, Twin Falls, Valley, Washington counties) and eastern Oregon
452 # switched four weeks late in 1974.
454 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
455 Zone America/Boise -7:44:49 - LMT 1883 Nov 18 12:15:11
456 -8:00 US P%sT 1923 May 13 2:00
458 -7:00 - MST 1974 Feb 3 2:00
463 # For a map of Indiana's time zone regions, see:
464 # <a href="http://www.mccsc.edu/time.html">
465 # What time is it in Indiana?
468 # From Paul Eggert (1995-12-19):
469 # Indiana generally observes either EST all year, or CST/CDT,
470 # but areas near Cincinnati and Louisville use those cities' timekeeping
471 # and in 1969 and 1970 the whole state observed daylight time;
472 # and there are other exceptions as noted below.
473 # Shanks partitions Indiana into 345 regions, each with its own time history,
474 # and writes ``Even newspaper reports present contradictory information.''
475 # Fortunately, most of the complexity occurred before our cutoff date of 1970.
477 # Since 1970, EST-only Indiana has been like America/Indianapolis,
478 # with exceptions noted below for Crawford, Starke, and Switzerland counties.
479 # The parts of Indiana not listed below have been like America/Chicago,
480 # America/Louisville, or America/New_York.
482 # Other than Indianapolis, the Indiana place names are so nondescript
483 # that they would be ambiguous if we left them at the `America' level.
484 # So we reluctantly put them all in a subdirectory `America/Indiana'.
486 # Most of EST-only Indiana last observed DST in 1970.
488 # From Paul Eggert (2001-03-06), following a tip by Markus Kuhn:
489 # Pam Belluck reported in the New York Times (2001-01-31) that the
490 # Indiana Legislature is considering a bill to adopt DST statewide.
491 # Her article mentioned Vevay, whose post office observes a different
492 # time zone from Danner's Hardware across the street.
494 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
495 Rule Indianapolis 1941 only - Jun 22 2:00 1:00 D
496 Rule Indianapolis 1941 1954 - Sep lastSun 2:00 0 S
497 Rule Indianapolis 1946 1954 - Apr lastSun 2:00 1:00 D
498 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
499 Zone America/Indianapolis -5:44:38 - LMT 1883 Nov 18 12:15:22
501 -6:00 Indianapolis C%sT 1942
503 -6:00 Indianapolis C%sT 1955 Apr 24 2:00
504 -5:00 - EST 1957 Sep 29 2:00
505 -6:00 - CST 1958 Apr 27 2:00
509 Link America/Indianapolis America/Indiana/Indianapolis
511 # Part of Crawford County, Indiana, last observed DST in 1975,
512 # and left its clocks alone in 1974.
513 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
514 Rule Marengo 1951 only - Apr lastSun 2:00 1:00 D
515 Rule Marengo 1951 only - Sep lastSun 2:00 0 S
516 Rule Marengo 1954 1960 - Apr lastSun 2:00 1:00 D
517 Rule Marengo 1954 1960 - Sep lastSun 2:00 0 S
518 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
519 Zone America/Indiana/Marengo -5:45:23 - LMT 1883 Nov 18 12:14:37
521 -6:00 Marengo C%sT 1961 Apr 30 2:00
523 -5:00 US E%sT 1974 Jan 6 2:00
524 -6:00 1:00 CDT 1974 Oct 27 2:00
528 # Starke County, Indiana
529 # From Arthur David Olson (1991-10-28):
530 # An article on page A3 of the Sunday, 1991-10-27 Washington Post
531 # notes that Starke County switched from Central time to Eastern time as of
533 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
534 Rule Starke 1947 1961 - Apr lastSun 2:00 1:00 D
535 Rule Starke 1947 1954 - Sep lastSun 2:00 0 S
536 Rule Starke 1955 1956 - Oct lastSun 2:00 0 S
537 Rule Starke 1957 1958 - Sep lastSun 2:00 0 S
538 Rule Starke 1959 1961 - Oct lastSun 2:00 0 S
539 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
540 Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 12:13:30
542 -6:00 Starke C%sT 1962 Apr 29 2:00
543 -5:00 - EST 1963 Oct 27 2:00
544 -6:00 US C%sT 1991 Oct 27 2:00
547 # Switzerland County, Indiana, last observed DST in 1972.
548 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
549 Zone America/Indiana/Vevay -5:40:16 - LMT 1883 Nov 18 12:19:44
550 -6:00 US C%sT 1954 Apr 25 2:00
555 # Part of Kentucky left its clocks alone in 1974.
556 # This also includes a part of Indiana immediately adjacent to Louisville.
557 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
558 Rule Louisville 1921 only - May 1 2:00 1:00 D
559 Rule Louisville 1921 only - Sep 1 2:00 0 S
560 Rule Louisville 1941 1961 - Apr lastSun 2:00 1:00 D
561 Rule Louisville 1941 only - Sep lastSun 2:00 0 S
562 Rule Louisville 1946 only - Jun 2 2:00 0 S
563 Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S
564 Rule Louisville 1956 1960 - Oct lastSun 2:00 0 S
565 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
566 Zone America/Louisville -5:43:02 - LMT 1883 Nov 18 12:16:58
568 -6:00 Louisville C%sT 1942
570 -6:00 Louisville C%sT 1961 Jul 23 2:00
572 -5:00 US E%sT 1974 Jan 6 2:00
573 -6:00 1:00 CDT 1974 Oct 27 2:00
575 Link America/Louisville America/Kentucky/Louisville
577 # Wayne, Clinton, and Russell Counties, Kentucky
580 # <a href="http://www.lake-cumberland.com/life/archive/news990129time.shtml">
581 # Lake Cumberland LIFE
582 # </a> (1999-01-29) via WKYM-101.7:
583 # Clinton County has joined Wayne County in asking the DoT to change from
584 # the Central to the Eastern time zone.... The Wayne County government made
585 # the same request in December. And while Russell County officials have not
586 # taken action, the majority of respondents to a poll conducted there in
587 # August indicated they would like to change to "fast time" also.
588 # The three Lake Cumberland counties are the farthest east of any U.S.
589 # location in the Central time zone.
591 # From Rich Wales (2000-08-29):
592 # After prolonged debate, and despite continuing deep differences of opinion,
593 # Wayne County (central Kentucky) is switching from Central (-0600) to Eastern
594 # (-0500) time. They won't "fall back" this year. See Sara Shipley,
595 # The difference an hour makes, Nando Times (2000-08-29 15:33 -0400).
597 # From Paul Eggert (2001-07-16):
598 # The final rule was published in the
599 # <a href="http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=2000_register&docid=fr17au00-22">
600 # Federal Register 65, 160 (2000-08-17), page 50154-50158.
603 Zone America/Kentucky/Monticello -5:39:24 - LMT 1883 Nov 18 12:20:36
606 -6:00 US C%sT 2000 Oct 29 2:00
610 # From Rives McDow (2000-08-30):
611 # Here ... are all the changes in the US since 1985.
612 # Kearny County, KS (put all of county on central;
613 # previously split between MST and CST) ... 1990-10
614 # Starke County, IN (from CST to EST) ... 1991-10
615 # Oliver County, ND (from MST to CST) ... 1992-10
616 # West Wendover, NV (from PST TO MST) ... 1999-10
617 # Wayne County, KY (from CST to EST) ... 2000-10
619 # From Paul Eggert (2001-07-17):
620 # We don't know where the line used to be within Kearny County, KS,
621 # so omit that change for now.
622 # See America/Indiana/Knox for the Starke County, IN change.
623 # See America/North_Dakota/Center for the Oliver County, ND change.
624 # West Wendover, NV officially switched from Pacific to mountain time on
625 # 1999-10-31. See the
626 # <a href="http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=1999_register&docid=fr21oc99-15">
627 # Federal Register 64, 203 (1999-10-21), page 56705-56707.
629 # However, the Federal Register says that West Wendover already operated
630 # on mountain time, and the rule merely made this official;
631 # hence a separate tz entry is not needed.
635 # From Bob Devine (1988-01-28):
636 # Michigan didn't observe DST from 1968 to 1973.
638 # From Paul Eggert (1999-03-31):
639 # Shanks writes that Michigan started using standard time on 1885-09-18,
640 # but Howse writes (pp 124-125, referring to Popular Astronomy, 1901-01)
643 # local time until 1900 when the City Council decreed that clocks should
644 # be put back twenty-eight minutes to Central Standard Time. Half the
645 # city obeyed, half refused. After considerable debate, the decision
646 # was rescinded and the city reverted to Sun time. A derisive offer to
647 # erect a sundial in front of the city hall was referred to the
648 # Committee on Sewers. Then, in 1905, Central time was adopted
651 # This story is too entertaining to be false, so go with Howse over Shanks.
653 # From Paul Eggert (2001-03-06):
654 # Garland (1927) writes ``Cleveland and Detroit advanced their clocks
655 # one hour in 1914.'' This change is not in Shanks. We have no more
656 # info, so omit this for now.
658 # Most of Michigan observed DST from 1973 on, but was a bit late in 1975.
659 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
660 Rule Detroit 1948 only - Apr lastSun 2:00 1:00 D
661 Rule Detroit 1948 only - Sep lastSun 2:00 0 S
662 Rule Detroit 1967 only - Jun 14 2:00 1:00 D
663 Rule Detroit 1967 only - Oct lastSun 2:00 0 S
664 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
665 Zone America/Detroit -5:32:11 - LMT 1905
666 -6:00 - CST 1915 May 15 2:00
669 -5:00 Detroit E%sT 1973
671 -5:00 - EST 1975 Apr 27 2:00
674 # The Michigan border with Wisconsin switched from EST to CST/CDT in 1973.
675 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
676 Rule Menominee 1946 only - Apr lastSun 2:00 1:00 D
677 Rule Menominee 1946 only - Sep lastSun 2:00 0 S
678 Rule Menominee 1966 only - Apr lastSun 2:00 1:00 D
679 Rule Menominee 1966 only - Oct lastSun 2:00 0 S
680 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
681 Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00
683 -6:00 Menominee C%sT 1969 Apr 27 2:00
684 -5:00 - EST 1973 Apr 29 2:00
688 # administered by the US Fish and Wildlife Service
689 # claimed by US under the provisions of the 1856 Guano Islands Act
690 # also claimed by Haiti
691 # occupied 1857/1900 by the Navassa Phosphate Co
692 # US lighthouse 1917/1996-09
693 # currently uninhabited
694 # see Mark Fineman, ``An Isle Rich in Guano and Discord'',
695 # _Los Angeles Times_ (1998-11-10), A1, A10; it cites
696 # Jimmy Skaggs, _The Great Guano Rush_ (1994).
698 # Old names, for S5 users
700 # Link LINK-FROM LINK-TO
701 Link America/New_York EST5EDT
702 Link America/Chicago CST6CDT
703 Link America/Denver MST7MDT
704 Link America/Los_Angeles PST8PDT
705 Link America/Indianapolis EST
706 Link America/Phoenix MST
707 Link Pacific/Honolulu HST
709 ################################################################################
712 # From Paul Eggert (1999-10-29):
713 # A good source for time zone historical data outside the US is
714 # Thomas G. Shanks, The International Atlas (5th edition),
715 # San Diego: ACS Publications, Inc. (1999).
717 # Gwillim Law writes that a good source
718 # for recent time zone data is the International Air Transport
719 # Association's Standard Schedules Information Manual (IATA SSIM),
720 # published semiannually. Law sent in several helpful summaries
721 # of the IATA's data after 1990.
723 # Except where otherwise noted, Shanks is the source for entries through 1990,
724 # and IATA SSIM is the source for entries after 1990.
726 # Other sources occasionally used include:
728 # Edward W. Whitman, World Time Differences,
729 # Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated),
730 # which I found in the UCLA library.
732 # <a href="http://www.pettswoodvillage.co.uk/Daylight_Savings_William_Willett.pdf">
733 # William Willett, The Waste of Daylight, 19th edition
736 # See the `europe' file for Greenland.
740 # From Alain LaBont<e'> <ALB@immedia.ca> (1994-11-14):
741 # I post here the time zone abbreviations standardized in Canada
742 # for both English and French in the CAN/CSA-Z234.4-89 standard....
744 # UTC Standard time Daylight savings time
745 # offset French English French English
756 # HN: Heure Normale ST: Standard Time
757 # HA: Heure Avanc<e'>e DT: Daylight saving Time
759 # A: de l'Atlantique Atlantic
760 # C: du Centre Central
761 # E: de l'Est Eastern
764 # P: du Pacifique Pacific
769 # From Paul Eggert (1994-11-22):
770 # Alas, this sort of thing must be handled by localization software.
772 # Unless otherwise specified, the data for Canada are all from Shanks.
774 # From Paul Eggert (2000-10-02):
775 # H. David Matthews and Mary Vincent's map
776 # <a href="http://www.canadiangeographic.ca/SO98/geomap.htm">
777 # "It's about TIME", _Canadian Geographic_ (September-October 1998)
778 # </a> contains detailed boundaries for regions observing nonstandard
779 # time and daylight saving time arrangements in Canada circa 1998.
781 # INMS, the Institute for National Measurement Standards in Ottawa, has
782 # <a href="http://www.nrc.ca/inms/time/tze.html">
783 # information about standard and daylight saving time zones in Canada.
784 # </a> (updated periodically).
785 # Its unofficial information is often taken from Matthews and Vincent.
787 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
788 Rule Canada 1918 only - Apr 14 2:00 1:00 D
789 Rule Canada 1918 only - Oct 31 2:00 0 S
790 Rule Canada 1942 only - Feb 9 2:00 1:00 W # War
791 Rule Canada 1945 only - Aug 14 23:00u 1:00 P # Peace
792 Rule Canada 1945 only - Sep 30 2:00 0 S
793 Rule Canada 1974 1986 - Apr lastSun 2:00 1:00 D
794 Rule Canada 1974 max - Oct lastSun 2:00 0 S
795 Rule Canada 1987 max - Apr Sun>=1 2:00 1:00 D
798 # Newfoundland (and far southeast Labrador)
800 # From Paul Eggert (2000-10-02):
801 # Matthews and Vincent (1998) write that Labrador should use NST/NDT,
802 # but the only part of Labrador that follows the rules is the
803 # southeast corner, including Port Hope Simpson and Mary's Harbour,
804 # but excluding, say, Black Tickle.
806 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
807 Rule StJohns 1917 only - Apr 8 2:00 1:00 D
808 Rule StJohns 1917 only - Sep 17 2:00 0 S
809 # Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks.
810 Rule StJohns 1919 only - May 5 23:00 1:00 D
811 Rule StJohns 1919 only - Aug 12 23:00 0 S
812 # For 1931-1935 Whitman gives Apr same date; go with Shanks.
813 Rule StJohns 1920 1935 - May Sun>=1 23:00 1:00 D
814 Rule StJohns 1920 1935 - Oct lastSun 23:00 0 S
815 # For 1936-1941 Whitman gives May Sun>=8 and Oct Sun>=1; go with Shanks.
816 Rule StJohns 1936 1941 - May Mon>=9 0:00 1:00 D
817 Rule StJohns 1936 1941 - Oct Mon>=2 0:00 0 S
818 # Whitman gives the following transitions:
819 # 1942 03-01/12-31, 1943 05-30/09-05, 1944 07-10/09-02, 1945 01-01/10-07
820 # but go with Shanks and assume they used Canadian rules.
821 # For 1946-9 Whitman gives May 5,4,9,1 - Oct 1,5,3,2, and for 1950 he gives
822 # Apr 30 - Sep 24; go with Shanks.
823 Rule StJohns 1946 1950 - May Sun>=8 2:00 1:00 D
824 Rule StJohns 1946 1950 - Oct Sun>=2 2:00 0 S
825 Rule StJohns 1951 1986 - Apr lastSun 2:00 1:00 D
826 Rule StJohns 1951 1959 - Sep lastSun 2:00 0 S
827 Rule StJohns 1960 1986 - Oct lastSun 2:00 0 S
828 # From Paul Eggert (2000-10-02):
829 # INMS (2000-09-12) says that, since 1988 at least, Newfoundland switches
830 # at 00:01 local time. For now, assume it started in 1987.
831 Rule StJohns 1987 only - Apr Sun>=1 0:01 1:00 D
832 Rule StJohns 1987 max - Oct lastSun 0:01 0 S
833 Rule StJohns 1988 only - Apr Sun>=1 0:01 2:00 DD
834 Rule StJohns 1989 max - Apr Sun>=1 0:01 1:00 D
835 # St John's has an apostrophe, but Posix file names can't have apostrophes.
836 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
837 Zone America/St_Johns -3:30:52 - LMT 1884
838 -3:30:52 StJohns N%sT 1918
839 -3:30:52 Canada N%sT 1919
840 -3:30:52 StJohns N%sT 1935 Mar 30
841 -3:30 StJohns N%sT 1942 May 11
842 -3:30 Canada N%sT 1946
845 # most of east Labrador
847 # The name `Happy Valley-Goose Bay' is too long; use `Goose Bay'.
848 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
849 Zone America/Goose_Bay -4:01:40 - LMT 1884 # Happy Valley-Goose Bay
851 -3:30:52 Canada N%sT 1919
852 -3:30:52 - NST 1935 Mar 30
854 -3:30 StJohns N%sT 1942 May 11
855 -3:30 Canada N%sT 1946
856 -3:30 StJohns N%sT 1966 Mar 15 2:00
860 # west Labrador, New Brunswick, Nova Scotia, Prince Edward I
862 # From Paul Eggert (1996-06-12):
863 # Shanks writes that since 1970 most of this region has been like Halifax.
864 # Many locales did not observe peacetime DST until 1972;
865 # Glace Bay, NS is the largest that we know of.
866 # Shanks also writes that Liverpool, NS was the only town in Canada to observe
867 # DST in 1971 but not 1970; for now we'll assume this is a typo.
869 # From Paul Eggert (2000-10-02):
870 # INMS (2000-09-12) says that, since 1988 at least, New Brunswick switches
871 # at 00:01 local time. FIXME: verify and create a new Zone for this.
874 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
875 Rule Halifax 1916 only - Apr 1 0:00 1:00 D
876 Rule Halifax 1916 only - Oct 1 0:00 0 S
877 Rule Halifax 1920 only - May 9 0:00 1:00 D
878 Rule Halifax 1920 only - Aug 29 0:00 0 S
879 Rule Halifax 1921 only - May 6 0:00 1:00 D
880 Rule Halifax 1921 1922 - Sep 5 0:00 0 S
881 Rule Halifax 1922 only - Apr 30 0:00 1:00 D
882 Rule Halifax 1923 1925 - May Sun>=1 0:00 1:00 D
883 Rule Halifax 1923 only - Sep 4 0:00 0 S
884 Rule Halifax 1924 only - Sep 15 0:00 0 S
885 Rule Halifax 1925 only - Sep 28 0:00 0 S
886 Rule Halifax 1926 only - May 16 0:00 1:00 D
887 Rule Halifax 1926 only - Sep 13 0:00 0 S
888 Rule Halifax 1927 only - May 1 0:00 1:00 D
889 Rule Halifax 1927 only - Sep 26 0:00 0 S
890 Rule Halifax 1928 1931 - May Sun>=8 0:00 1:00 D
891 Rule Halifax 1928 only - Sep 9 0:00 0 S
892 Rule Halifax 1929 only - Sep 3 0:00 0 S
893 Rule Halifax 1930 only - Sep 15 0:00 0 S
894 Rule Halifax 1931 1932 - Sep Mon>=24 0:00 0 S
895 Rule Halifax 1932 only - May 1 0:00 1:00 D
896 Rule Halifax 1933 only - Apr 30 0:00 1:00 D
897 Rule Halifax 1933 only - Oct 2 0:00 0 S
898 Rule Halifax 1934 only - May 20 0:00 1:00 D
899 Rule Halifax 1934 only - Sep 16 0:00 0 S
900 Rule Halifax 1935 only - Jun 2 0:00 1:00 D
901 Rule Halifax 1935 only - Sep 30 0:00 0 S
902 Rule Halifax 1936 only - Jun 1 0:00 1:00 D
903 Rule Halifax 1936 only - Sep 14 0:00 0 S
904 Rule Halifax 1937 1938 - May Sun>=1 0:00 1:00 D
905 Rule Halifax 1937 1941 - Sep Mon>=24 0:00 0 S
906 Rule Halifax 1939 only - May 28 0:00 1:00 D
907 Rule Halifax 1940 1941 - May Sun>=1 0:00 1:00 D
908 Rule Halifax 1946 1949 - Sep lastSun 2:00 0 S
909 Rule Halifax 1946 1949 - Apr lastSun 2:00 1:00 D
910 Rule Halifax 1951 1954 - Sep lastSun 2:00 0 S
911 Rule Halifax 1951 1954 - Apr lastSun 2:00 1:00 D
912 Rule Halifax 1956 1959 - Sep lastSun 2:00 0 S
913 Rule Halifax 1956 1959 - Apr lastSun 2:00 1:00 D
914 Rule Halifax 1962 1973 - Apr lastSun 2:00 1:00 D
915 Rule Halifax 1962 1973 - Oct lastSun 2:00 0 S
916 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
917 Zone America/Halifax -4:14:24 - LMT 1902 Jun 15
918 -4:00 Halifax A%sT 1918
919 -4:00 Canada A%sT 1919
920 -4:00 Halifax A%sT 1942 Feb 9 2:00s
921 -4:00 Canada A%sT 1946
922 -4:00 Halifax A%sT 1974
924 Zone America/Glace_Bay -3:59:48 - LMT 1902 Jun 15
925 -4:00 Canada A%sT 1953
926 -4:00 Halifax A%sT 1954
928 -4:00 Halifax A%sT 1974
934 # From Paul Eggert (1996-06-12):
935 # Shanks writes that since 1970 most of Ontario has been like Toronto,
936 # and most of Quebec has been like Montreal.
937 # Thunder Bay skipped DST in 1973.
938 # Many smaller locales did not observe peacetime DST until 1974;
939 # Nipigon (EST) and Rainy River (CST) are the largest that we know of.
940 # Far west Ontario is like Winnipeg; far east Quebec is like Halifax.
942 # From Mark Brader (2003-07-26):
943 # [According to the Toronto Star] Orillia, Ontario, adopted DST
944 # effective Saturday, 1912-06-22, 22:00; the article mentions that
945 # Port Arthur (now part of Thunder Bay, Ontario) as well as Moose Jaw
946 # have already done so. In Orillia DST was to run until Saturday,
947 # 1912-08-31 (no time mentioned), but it was met with considerable
948 # hostility from certain segments of the public, and was revoked after
949 # only two weeks -- I copied it as Saturday, 1912-07-07, 22:00, but
950 # presumably that should be -07-06. (1912-06-19, -07-12; also letters
953 # Kenora, Ontario, was to abandon DST on 1914-06-01 (-05-21).
955 # From Paul Eggert (1997-10-17):
956 # Mark Brader writes that an article in the 1997-10-14 Toronto Star
957 # says that Atikokan, Ontario currently does not observe DST,
958 # but will vote on 11-10 whether to use EST/EDT.
959 # He also writes that the
960 # <a href="http://www.gov.on.ca/MBS/english/publications/statregs/conttext.html">
961 # Ontario Time Act (1990, Chapter T.9)
963 # says that Ontario east of 90W uses EST/EDT, and west of 90W uses CST/CDT.
964 # Officially Atikokan is therefore on CST/CDT, and most likely this report
965 # concerns a non-official time observed as a matter of local practice.
966 # For what it's worth, Shanks says that Atikokan has agreed with
967 # Rainy River ever since standard time was introduced.
969 # From Paul Eggert (2000-10-02):
970 # Matthews and Vincent (1998) write that Atikokan, Pickle Lake, and
971 # New Osnaburgh observe CST all year, that Big Trout Lake observes
972 # CST/CDT, and that Upsala and Shebandowan observe EST/EDT, all in
973 # violation of the official Ontario rules.
974 # They also write that Quebec east of the -63 meridian is supposed to
975 # observe AST, but residents as far east as Natashquan use EST/EDT,
976 # and residents east of Natashquan use AST.
977 # We probably need Zones for far east Quebec and for Atikokan,
978 # but we don't know when their practices started.
980 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
981 Rule Mont 1917 only - Mar 25 2:00 1:00 D
982 Rule Mont 1917 only - Apr 24 0:00 0 S
983 Rule Mont 1919 only - Mar 31 2:30 1:00 D
984 Rule Mont 1919 only - Oct 25 2:30 0 S
985 Rule Mont 1920 only - May 2 2:30 1:00 D
986 Rule Mont 1920 1922 - Oct Sun>=1 2:30 0 S
987 Rule Mont 1921 only - May 1 2:00 1:00 D
988 Rule Mont 1922 only - Apr 30 2:00 1:00 D
989 Rule Mont 1924 only - May 17 2:00 1:00 D
990 Rule Mont 1924 1926 - Sep lastSun 2:30 0 S
991 Rule Mont 1925 1926 - May Sun>=1 2:00 1:00 D
992 # The 1927-to-1937 rules can be expressed more simply as
993 # Rule Mont 1927 1937 - Apr lastSat 24:00 1:00 D
994 # Rule Mont 1927 1937 - Sep lastSat 24:00 0 S
995 # The rules below avoid use of 24:00
996 # (which pre-1998 versions of zic cannot handle).
997 Rule Mont 1927 only - May 1 0:00 1:00 D
998 Rule Mont 1927 1932 - Sep lastSun 0:00 0 S
999 Rule Mont 1928 1931 - Apr lastSun 0:00 1:00 D
1000 Rule Mont 1932 only - May 1 0:00 1:00 D
1001 Rule Mont 1933 1940 - Apr lastSun 0:00 1:00 D
1002 Rule Mont 1933 only - Oct 1 0:00 0 S
1003 Rule Mont 1934 1939 - Sep lastSun 0:00 0 S
1004 Rule Mont 1946 1973 - Apr lastSun 2:00 1:00 D
1005 Rule Mont 1945 1948 - Sep lastSun 2:00 0 S
1006 Rule Mont 1949 1950 - Oct lastSun 2:00 0 S
1007 Rule Mont 1951 1956 - Sep lastSun 2:00 0 S
1008 Rule Mont 1957 1973 - Oct lastSun 2:00 0 S
1010 Rule Toronto 1919 only - Mar 30 23:30 1:00 D
1011 Rule Toronto 1919 only - Oct 26 0:00 0 S
1012 Rule Toronto 1920 only - May 2 2:00 1:00 D
1013 Rule Toronto 1920 only - Sep 26 0:00 0 S
1014 Rule Toronto 1921 only - May 15 2:00 1:00 D
1015 Rule Toronto 1921 only - Sep 15 2:00 0 S
1016 Rule Toronto 1922 1923 - May Sun>=8 2:00 1:00 D
1017 # Shanks says 1923-09-19; assume it's a typo and that "-16" was meant.
1018 Rule Toronto 1922 1926 - Sep Sun>=15 2:00 0 S
1019 Rule Toronto 1924 1927 - May Sun>=1 2:00 1:00 D
1020 # The 1927-to-1939 rules can be expressed more simply as
1021 # Rule Toronto 1927 1937 - Sep Sun>=25 2:00 0 S
1022 # Rule Toronto 1928 1937 - Apr Sun>=25 2:00 1:00 D
1023 # Rule Toronto 1938 1940 - Apr lastSun 2:00 1:00 D
1024 # Rule Toronto 1938 1939 - Sep lastSun 2:00 0 S
1025 # The rules below avoid use of Sun>=25
1026 # (which pre-2004 versions of zic cannot handle).
1027 Rule Toronto 1927 1932 - Sep lastSun 2:00 0 S
1028 Rule Toronto 1928 1931 - Apr lastSun 2:00 1:00 D
1029 Rule Toronto 1932 only - May 1 2:00 1:00 D
1030 Rule Toronto 1933 1940 - Apr lastSun 2:00 1:00 D
1031 Rule Toronto 1933 only - Oct 1 2:00 0 S
1032 Rule Toronto 1934 1939 - Sep lastSun 2:00 0 S
1033 Rule Toronto 1945 1946 - Sep lastSun 2:00 0 S
1034 Rule Toronto 1946 only - Apr lastSun 2:00 1:00 D
1035 Rule Toronto 1947 1949 - Apr lastSun 0:00 1:00 D
1036 Rule Toronto 1947 1948 - Sep lastSun 0:00 0 S
1037 Rule Toronto 1949 only - Nov lastSun 0:00 0 S
1038 Rule Toronto 1950 1973 - Apr lastSun 2:00 1:00 D
1039 Rule Toronto 1950 only - Nov lastSun 2:00 0 S
1040 Rule Toronto 1951 1956 - Sep lastSun 2:00 0 S
1041 # Shanks says Toronto ended DST a week early in 1971, namely on 1971-10-24,
1042 # but Mark Brader wrote (2003-05-31) that he checked the 1971-10-30 issue
1043 # of the Toronto Star, and it said that DST ended 1971-10-31 as usual.
1044 Rule Toronto 1957 1973 - Oct lastSun 2:00 0 S
1046 # From Paul Eggert (2003-07-27):
1047 # Willett (1914-03) writes (p. 17) "In the Cities of Fort William, and
1048 # Port Arthur, Ontario, the principle of the Bill has been in
1049 # operation for the past three years, and in the City of Moose Jaw,
1050 # Saskatchewan, for one year."
1052 # From David Bryan via Tory Tronrud, Director/Curator,
1053 # Thunder Bay Museum (2003-11-12):
1054 # There is some suggestion, however, that, by-law or not, daylight
1055 # savings time was being practiced in Fort William and Port Arthur
1056 # before 1909.... [I]n 1910, the line between the Eastern and Central
1057 # Time Zones was permanently moved about two hundred miles west to
1058 # include the Thunder Bay area.... When Canada adopted daylight
1059 # savings time in 1916, Fort William and Port Arthur, having done so
1060 # already, did not change their clocks.... During the Second World
1061 # War,... [t]he cities agreed to implement DST during the summer
1062 # months for the remainder of the war years.
1064 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1065 Zone America/Montreal -4:54:16 - LMT 1884
1066 -5:00 Mont E%sT 1918
1067 -5:00 Canada E%sT 1919
1068 -5:00 Mont E%sT 1942 Feb 9 2:00s
1069 -5:00 Canada E%sT 1946
1070 -5:00 Mont E%sT 1974
1072 Zone America/Toronto -5:17:32 - LMT 1895
1073 -5:00 Canada E%sT 1919
1074 -5:00 Toronto E%sT 1942 Feb 9 2:00s
1075 -5:00 Canada E%sT 1946
1076 -5:00 Toronto E%sT 1974
1078 Zone America/Thunder_Bay -5:57:00 - LMT 1895
1081 -5:00 Canada E%sT 1970
1082 -5:00 Mont E%sT 1973
1085 Zone America/Nipigon -5:53:04 - LMT 1895
1086 -5:00 Canada E%sT 1940 Sep 29
1087 -5:00 1:00 EDT 1942 Feb 9 2:00s
1089 Zone America/Rainy_River -6:17:56 - LMT 1895
1090 -6:00 Canada C%sT 1940 Sep 29
1091 -6:00 1:00 CDT 1942 Feb 9 2:00s
1097 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1098 Rule Winn 1916 only - Apr 23 0:00 1:00 D
1099 Rule Winn 1916 only - Sep 17 0:00 0 S
1100 Rule Winn 1918 only - Apr 14 2:00 1:00 D
1101 Rule Winn 1918 only - Oct 31 2:00 0 S
1102 Rule Winn 1937 only - May 16 2:00 1:00 D
1103 Rule Winn 1937 only - Sep 26 2:00 0 S
1104 Rule Winn 1942 only - Feb 9 2:00 1:00 W # War
1105 Rule Winn 1945 only - Aug 14 23:00u 1:00 P # Peace
1106 Rule Winn 1945 only - Sep lastSun 2:00 0 S
1107 Rule Winn 1946 only - May 12 2:00 1:00 D
1108 Rule Winn 1946 only - Oct 13 2:00 0 S
1109 Rule Winn 1947 1949 - Apr lastSun 2:00 1:00 D
1110 Rule Winn 1947 1949 - Sep lastSun 2:00 0 S
1111 Rule Winn 1950 only - May 1 2:00 1:00 D
1112 Rule Winn 1950 only - Sep 30 2:00 0 S
1113 Rule Winn 1951 1960 - Apr lastSun 2:00 1:00 D
1114 Rule Winn 1951 1958 - Sep lastSun 2:00 0 S
1115 Rule Winn 1959 only - Oct lastSun 2:00 0 S
1116 Rule Winn 1960 only - Sep lastSun 2:00 0 S
1117 Rule Winn 1963 only - Apr lastSun 2:00 1:00 D
1118 Rule Winn 1963 only - Sep 22 2:00 0 S
1119 Rule Winn 1966 1986 - Apr lastSun 2:00 1:00 D
1120 Rule Winn 1966 1986 - Oct lastSun 2:00 0 S
1121 Rule Winn 1987 max - Apr Sun>=1 2:00 1:00 D
1122 # From Paul Eggert (2000-10-02):
1123 # INMS (2000-09-12) says that, since 1988 at least, Manitoba switches from
1124 # DST at 03:00 local time. For now, assume it started in 1987.
1125 Rule Winn 1987 max - Oct lastSun 2:00s 0 S
1126 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1127 Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16
1133 # From Mark Brader (2003-07-26):
1134 # The first actual adoption of DST in Canada was at the municipal
1135 # level. As the [Toronto] Star put it (1912-06-07), "While people
1136 # elsewhere have long been talking of legislation to save daylight,
1137 # the city of Moose Jaw [Saskatchewan] has acted on its own hook."
1138 # DST in Moose Jaw began on Saturday, 1912-06-01 (no time mentioned:
1139 # presumably late evening, as below), and would run until "the end of
1140 # the summer". The discrepancy between municipal time and railroad
1143 # From Paul Eggert (2003-07-27):
1144 # Willett (1914-03) notes that DST "has been in operation ... in the
1145 # City of Moose Jaw, Saskatchewan, for one year."
1147 # From Paul Eggert (2000-10-02):
1148 # Shanks writes that since 1970 most of this region has been like Regina.
1149 # Some western towns (e.g. Swift Current) switched from MST/MDT to CST in 1972.
1150 # Other western towns (e.g. Lloydminster) are like Edmonton.
1151 # Matthews and Vincent (1998) write that Denare Beach and Creighton
1152 # are like Winnipeg, in violation of Saskatchewan law.
1154 # From W. Jones <jones@skdad.usask.ca> (1992-11-06):
1155 # The. . .below is based on information I got from our law library, the
1156 # provincial archives, and the provincial Community Services department.
1157 # A precise history would require digging through newspaper archives, and
1158 # since you didn't say what you wanted, I didn't bother.
1160 # Saskatchewan is split by a time zone meridian (105W) and over the years
1161 # the boundary became pretty ragged as communities near it reevaluated
1162 # their affiliations in one direction or the other. In 1965 a provincial
1163 # referendum favoured legislating common time practices.
1165 # On 15 April 1966 the Time Act (c. T-14, Revised Statutes of
1166 # Saskatchewan 1978) was proclaimed, and established that the eastern
1167 # part of Saskatchewan would use CST year round, that districts in
1168 # northwest Saskatchewan would by default follow CST but could opt to
1169 # follow Mountain Time rules (thus 1 hour difference in the winter and
1170 # zero in the summer), and that districts in southwest Saskatchewan would
1171 # by default follow MT but could opt to follow CST.
1173 # It took a few years for the dust to settle (I know one story of a town
1174 # on one time zone having its school in another, such that a mom had to
1175 # serve her family lunch in two shifts), but presently it seems that only
1176 # a few towns on the border with Alberta (e.g. Lloydminster) follow MT
1177 # rules any more; all other districts appear to have used CST year round
1178 # since sometime in the 1960s.
1180 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1181 Rule Regina 1918 only - Apr 14 2:00 1:00 D
1182 Rule Regina 1918 only - Oct 31 2:00 0 S
1183 Rule Regina 1930 1934 - May Sun>=1 0:00 1:00 D
1184 Rule Regina 1930 1934 - Oct Sun>=1 0:00 0 S
1185 Rule Regina 1937 1941 - Apr Sun>=8 0:00 1:00 D
1186 Rule Regina 1937 only - Oct Sun>=8 0:00 0 S
1187 Rule Regina 1938 only - Oct Sun>=1 0:00 0 S
1188 Rule Regina 1939 1941 - Oct Sun>=8 0:00 0 S
1189 Rule Regina 1942 only - Feb 9 2:00 1:00 W # War
1190 Rule Regina 1945 only - Aug 14 23:00u 1:00 P # Peace
1191 Rule Regina 1945 only - Sep lastSun 2:00 0 S
1192 Rule Regina 1946 only - Apr Sun>=8 2:00 1:00 D
1193 Rule Regina 1946 only - Oct Sun>=8 2:00 0 S
1194 Rule Regina 1947 1957 - Apr lastSun 2:00 1:00 D
1195 Rule Regina 1947 1957 - Sep lastSun 2:00 0 S
1196 Rule Regina 1959 only - Apr lastSun 2:00 1:00 D
1197 Rule Regina 1959 only - Oct lastSun 2:00 0 S
1199 Rule Swift 1957 only - Apr lastSun 2:00 1:00 D
1200 Rule Swift 1957 only - Oct lastSun 2:00 0 S
1201 Rule Swift 1959 1961 - Apr lastSun 2:00 1:00 D
1202 Rule Swift 1959 only - Oct lastSun 2:00 0 S
1203 Rule Swift 1960 1961 - Sep lastSun 2:00 0 S
1204 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1205 Zone America/Regina -6:58:36 - LMT 1905 Sep
1206 -7:00 Regina M%sT 1960 Apr lastSun 2:00
1208 Zone America/Swift_Current -7:11:20 - LMT 1905 Sep
1209 -7:00 Canada M%sT 1946 Apr lastSun 2:00
1210 -7:00 Regina M%sT 1950
1211 -7:00 Swift M%sT 1972 Apr lastSun 2:00
1217 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1218 Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D
1219 Rule Edm 1918 only - Oct 31 2:00 0 S
1220 Rule Edm 1919 only - May 27 2:00 0 S
1221 Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D
1222 Rule Edm 1920 only - Oct lastSun 2:00 0 S
1223 Rule Edm 1921 1923 - Sep lastSun 2:00 0 S
1224 Rule Edm 1942 only - Feb 9 2:00 1:00 W # War
1225 Rule Edm 1945 only - Aug 14 23:00u 1:00 P # Peace
1226 Rule Edm 1945 only - Sep lastSun 2:00 0 S
1227 Rule Edm 1947 only - Apr lastSun 2:00 1:00 D
1228 Rule Edm 1947 only - Sep lastSun 2:00 0 S
1229 Rule Edm 1967 only - Apr lastSun 2:00 1:00 D
1230 Rule Edm 1967 only - Oct lastSun 2:00 0 S
1231 Rule Edm 1969 only - Apr lastSun 2:00 1:00 D
1232 Rule Edm 1969 only - Oct lastSun 2:00 0 S
1233 Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D
1234 Rule Edm 1972 max - Oct lastSun 2:00 0 S
1235 Rule Edm 1987 max - Apr Sun>=1 2:00 1:00 D
1236 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1237 Zone America/Edmonton -7:33:52 - LMT 1906 Sep
1243 # From Paul Eggert (2000-10-02):
1244 # Shanks writes that since 1970 most of this region has been like Vancouver.
1245 # Dawson Creek uses MST. Much of east BC is like Edmonton.
1246 # Matthews and Vincent (1998) write that Creston is like Dawson Creek.
1248 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1249 Rule Vanc 1918 only - Apr 14 2:00 1:00 D
1250 Rule Vanc 1918 only - Oct 31 2:00 0 S
1251 Rule Vanc 1942 only - Feb 9 2:00 1:00 W # War
1252 Rule Vanc 1945 only - Aug 14 23:00u 1:00 P # Peace
1253 Rule Vanc 1945 only - Sep 30 2:00 0 S
1254 Rule Vanc 1946 1986 - Apr lastSun 2:00 1:00 D
1255 Rule Vanc 1946 only - Oct 13 2:00 0 S
1256 Rule Vanc 1947 1961 - Sep lastSun 2:00 0 S
1257 Rule Vanc 1962 max - Oct lastSun 2:00 0 S
1258 Rule Vanc 1987 max - Apr Sun>=1 2:00 1:00 D
1259 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1260 Zone America/Vancouver -8:12:28 - LMT 1884
1262 Zone America/Dawson_Creek -8:00:56 - LMT 1884
1263 -8:00 Canada P%sT 1947
1264 -8:00 Vanc P%sT 1972 Aug 30 2:00
1268 # Northwest Territories, Nunavut, Yukon
1270 # From Paul Eggert (1999-10-29):
1271 # Dawson switched to PST in 1973. Inuvik switched to MST in 1979.
1272 # Mathew Englander <mathew@io.org> (1996-10-07) gives the following refs:
1273 # * 1967. Paragraph 28(34)(g) of the Interpretation Act, S.C. 1967-68,
1274 # c. 7 defines Yukon standard time as UTC-9. This is still valid;
1275 # see Interpretation Act, R.S.C. 1985, c. I-21, s. 35(1).
1276 # * C.O. 1973/214 switched Yukon to PST on 1973-10-28 00:00.
1277 # * O.I.C. 1980/02 established DST.
1278 # * O.I.C. 1987/056 changed DST to Apr firstSun 2:00 to Oct lastSun 2:00.
1279 # Shanks says Yukon's 1973-10-28 switch was at 2:00; go with Englander.
1281 # From Rives McDow (1999-09-04):
1282 # Nunavut ... moved ... to incorporate the whole territory into one time zone.
1283 # <a href="http://www.nunatsiaq.com/nunavut/nvt90903_13.html">
1284 # Nunavut moves to single time zone Oct. 31
1287 # From Antoine Leca (1999-09-06):
1288 # We then need to create a new timezone for the Kitikmeot region of Nunavut
1289 # to differentiate it from the Yellowknife region.
1291 # From Paul Eggert (1999-09-20):
1292 # <a href="http://www.nunavut.com/basicfacts/english/basicfacts_1territory.html">
1293 # Basic Facts: The New Territory
1294 # </a> (1999) reports that Pangnirtung operates on eastern time,
1295 # and that Coral Harbour does not observe DST. We don't know when
1296 # Pangnirtung switched to eastern time; we'll guess 1995.
1297 # We'll ignore the claim about Coral Harbour for now,
1298 # since we have no further info.
1300 # From Rives McDow (1999-11-08):
1301 # On October 31, when the rest of Nunavut went to Central time,
1302 # Pangnirtung wobbled. Here is the result of their wobble:
1304 # The following businesses and organizations in Pangnirtung use Central Time:
1306 # First Air, Power Corp, Nunavut Construction, Health Center, RCMP,
1307 # Eastern Arctic National Parks, A & D Specialist
1309 # The following businesses and organizations in Pangnirtung use Eastern Time:
1311 # Hamlet office, All other businesses, Both schools, Airport operator
1313 # This has made for an interesting situation there, which warranted the news.
1314 # No one there that I spoke with seems concerned, or has plans to
1315 # change the local methods of keeping time, as it evidently does not
1316 # really interfere with any activities or make things difficult locally.
1317 # They plan to celebrate New Year's turn-over twice, one hour apart,
1318 # so it appears that the situation will last at least that long.
1319 # The Nunavut Intergovernmental Affairs hopes that they will "come to
1320 # their senses", but the locals evidently don't see any problem with
1321 # the current state of affairs.
1323 # From Michaela Rodrigue, writing in the
1324 # <a href="http://www.nunatsiaq.com/archives/nunavut991130/nvt91119_17.html">
1325 # Nunatsiaq News (1999-11-19)</a>:
1326 # Clyde River, Pangnirtung and Sanikiluaq now operate with two time zones,
1327 # central - or Nunavut time - for government offices, and eastern time
1328 # for municipal offices and schools.... Igloolik [was similar but then]
1329 # made the switch to central time on Saturday, Nov. 6.
1331 # From Paul Eggert (2000-10-02):
1332 # Matthews and Vincent (1998) say the following, but we lack histories
1333 # for these potential new Zones.
1335 # The Canadian Forces station at Alert uses Eastern Time while the
1336 # handful of residents at the Eureka weather station [in the Central
1337 # zone] skip daylight savings. Baffin Island, which is crossed by the
1338 # Central, Eastern and Atlantic Time zones only uses Eastern Time.
1339 # Gjoa Haven, Taloyoak and Pelly Bay all use Mountain instead of
1340 # Central Time and Southampton Island [in the Central zone] is not
1341 # required to use daylight savings.
1344 # <a href="http://www.nunatsiaq.com/archives/nunavut001130/nvt21110_02.html">
1345 # Nunavut now has two time zones
1346 # </a> (2000-11-10):
1347 # The Nunavut government would allow its employees in Kugluktuk and
1348 # Cambridge Bay to operate on central time year-round, putting them
1349 # one hour behind the rest of Nunavut for six months during the winter.
1350 # At the end of October the two communities had rebelled against
1351 # Nunavut's unified time zone, refusing to shift to eastern time with
1352 # the rest of the territory for the winter. Cambridge Bay remained on
1353 # central time, while Kugluktuk, even farther west, reverted to
1354 # mountain time, which they had used before the advent of Nunavut's
1355 # unified time zone in 1999.
1357 # From Rives McDow (2001-01-20), quoting the Nunavut government:
1358 # The preceding decision came into effect at midnight, Saturday Nov 4, 2000.
1360 # From Paul Eggert (2000-12-04):
1361 # Let's just keep track of the official times for now.
1363 # From Rives McDow (2001-03-07):
1364 # The premier of Nunavut has issued a ministerial statement advising
1365 # that effective 2001-04-01, the territory of Nunavut will revert
1366 # back to three time zones (mountain, central, and eastern). Of the
1367 # cities in Nunavut, Coral Harbor is the only one that I know of that
1368 # has said it will not observe dst, staying on EST year round. I'm
1369 # checking for more info, and will get back to you if I come up with
1371 # [Also see <http://www.nunatsiaq.com/nunavut/nvt10309_06.html> (2001-03-09).]
1373 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1374 Rule NT_YK 1918 only - Apr 14 2:00 1:00 D
1375 Rule NT_YK 1918 only - Oct 27 2:00 0 S
1376 Rule NT_YK 1919 only - May 25 2:00 1:00 D
1377 Rule NT_YK 1919 only - Nov 1 0:00 0 S
1378 Rule NT_YK 1942 only - Feb 9 2:00 1:00 W # War
1379 Rule NT_YK 1945 only - Aug 14 23:00u 1:00 P # Peace
1380 Rule NT_YK 1945 only - Sep 30 2:00 0 S
1381 Rule NT_YK 1965 only - Apr lastSun 0:00 2:00 DD
1382 Rule NT_YK 1965 only - Oct lastSun 2:00 0 S
1383 Rule NT_YK 1980 1986 - Apr lastSun 2:00 1:00 D
1384 Rule NT_YK 1980 max - Oct lastSun 2:00 0 S
1385 Rule NT_YK 1987 max - Apr Sun>=1 2:00 1:00 D
1386 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1387 Zone America/Pangnirtung -4:22:56 - LMT 1884
1388 -4:00 NT_YK A%sT 1995 Apr Sun>=1 2:00
1389 -5:00 Canada E%sT 1999 Oct 31 2:00
1390 -6:00 Canada C%sT 2000 Oct 29 2:00
1392 Zone America/Iqaluit -4:33:52 - LMT 1884 # Frobisher Bay before 1987
1393 -5:00 NT_YK E%sT 1999 Oct 31 2:00
1394 -6:00 Canada C%sT 2000 Oct 29 2:00
1396 Zone America/Rankin_Inlet -6:08:40 - LMT 1884
1397 -6:00 NT_YK C%sT 2000 Oct 29 2:00
1398 -5:00 - EST 2001 Apr 1 3:00
1400 Zone America/Cambridge_Bay -7:00:20 - LMT 1884
1401 -7:00 NT_YK M%sT 1999 Oct 31 2:00
1402 -6:00 Canada C%sT 2000 Oct 29 2:00
1403 -5:00 - EST 2000 Nov 5 0:00
1404 -6:00 - CST 2001 Apr 1 3:00
1406 Zone America/Yellowknife -7:37:24 - LMT 1884
1408 Zone America/Inuvik -8:54:00 - LMT 1884
1409 -8:00 NT_YK P%sT 1979 Apr lastSun 2:00
1411 Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20
1412 -9:00 NT_YK Y%sT 1966 Jul 1 2:00
1414 Zone America/Dawson -9:17:40 - LMT 1900 Aug 20
1415 -9:00 NT_YK Y%sT 1973 Oct 28 0:00
1419 ###############################################################################
1423 # From Paul Eggert (2001-03-05):
1424 # The Investigation and Analysis Service of the
1425 # Mexican Library of Congress (MLoC) has published a
1426 # <a href="http://www.cddhcu.gob.mx/bibliot/publica/inveyana/polisoc/horver/">
1427 # history of Mexican local time (in Spanish)
1430 # Here are the discrepancies between Shanks and the MLoC.
1431 # (In all cases we go with the MLoC.)
1432 # Shanks reports that Baja was at -8:00 in 1922/1923.
1433 # Shanks says the 1930 transition in Baja was 1930-11-16.
1434 # Shanks reports no DST during summer 1931.
1435 # Shanks reports a transition at 1932-03-30 23:00, not 1932-04-01.
1436 # Shanks does not report transitions for Baja in 1945 or 1948.
1437 # Shanks reports southern Mexico transitions on 1981-12-01, not 12-23.
1438 # Shanks says Quintana Roo switched to -6:00 on 1982-12-02, and to -5:00
1439 # on 1997-10-26 at 02:00.
1441 # From Gwillim Law (2001-02-20):
1442 # There are some other discrepancies between the Decrees page and the
1443 # tz database. I think they can best be explained by supposing that
1444 # the researchers who prepared the Decrees page failed to find some of
1445 # the relevant documents.
1447 # From Paul Eggert (2000-07-26):
1448 # Shanks gives 1942-04-01 instead of 1942-04-24, and omits the 1981
1449 # and 1988 DST experiments. Go with spin.com.mx.
1451 # From Alan Perry <alan.perry@eng.sun.com> (1996-02-15):
1452 # A guy from our Mexico subsidiary finally found the Presidential Decree
1453 # outlining the timezone changes in Mexico.
1455 # ------------- Begin Forwarded Message -------------
1457 # I finally got my hands on the Official Presidential Decree that sets up the
1458 # rules for the DST changes. The rules are:
1460 # 1. The country is divided in 3 timezones:
1461 # - Baja California Norte (the Mexico/BajaNorte TZ)
1462 # - Baja California Sur, Nayarit, Sinaloa and Sonora (the Mexico/BajaSur TZ)
1463 # - The rest of the country (the Mexico/General TZ)
1465 # 2. From the first Sunday in April at 2:00 AM to the last Sunday in October
1466 # at 2:00 AM, the times in each zone are as follows:
1471 # 3. The rest of the year, the times are as follows:
1476 # The Decree was published in Mexico's Official Newspaper on January 4th.
1478 # -------------- End Forwarded Message --------------
1479 # From Paul Eggert (1996-06-12):
1480 # For an English translation of the decree, see
1481 # <a href="http://mexico-travel.com/extra/timezone_eng.html">
1482 # ``Diario Oficial: Time Zone Changeover'' (1996-01-04).
1485 # From Rives McDow (1998-10-08):
1486 # The State of Quintana Roo has reverted back to central STD and DST times
1487 # (i.e. UTC -0600 and -0500 as of 1998-08-02).
1489 # From Rives McDow (2000-01-10):
1490 # Effective April 4, 1999 at 2:00 AM local time, Sonora changed to the time
1491 # zone 5 hours from the International Date Line, and will not observe daylight
1492 # savings time so as to stay on the same time zone as the southern part of
1493 # Arizona year round.
1495 # From Jesper Norgaard, translating
1496 # <http://www.reforma.com/nacional/articulo/064327/> (2001-01-17):
1497 # In Oaxaca, the 55.000 teachers from the Section 22 of the National
1498 # Syndicate of Education Workers, refuse to apply daylight saving each
1499 # year, so that the more than 10,000 schools work at normal hour the
1502 # From Gwillim Law (2001-01-19):
1503 # <http://www.reforma.com/negocios_y_dinero/articulo/064481/> ... says
1505 # January 17, 2000 - The Energy Secretary, Ernesto Martens, announced
1506 # that Summer Time will be reduced from seven to five months, starting
1508 # <http://www.publico.com.mx/scripts/texto3.asp?action=pagina&pag=21&pos=p&secc=naci&date=01/17/2001>
1509 # [translated], says "summer time will ... take effect on the first Sunday
1510 # in May, and end on the last Sunday of September.
1512 # From Arthur David Olson (2001-01-25):
1513 # The 2001-01-24 traditional Washington Post contained the page one
1514 # story "Timely Issue Divides Mexicans."...
1515 # http://www.washingtonpost.com/wp-dyn/articles/A37383-2001Jan23.html
1516 # ... Mexico City Mayor Lopez Obrador "...is threatening to keep
1517 # Mexico City and its 20 million residents on a different time than
1518 # the rest of the country..." In particular, Lopez Obrador would abolish
1519 # observation of Daylight Saving Time.
1521 # <a href="http://www.conae.gob.mx/ahorro/decretohorver2001.html#decre">
1522 # Official statute published by the Energy Department
1523 # </a> (2001-02-01) shows Baja and Chihauhua as still using US DST rules,
1524 # and Sonora with no DST. This was reported by Jesper Norgaard (2001-02-03).
1526 # From Paul Eggert (2001-03-03):
1528 # <a href="http://www.latimes.com/news/nation/20010303/t000018766.html">
1529 # James F. Smith writes in today's LA Times
1531 # * Sonora will continue to observe standard time.
1532 # * Last week Mexico City's mayor Andres Manuel Lopez Obrador decreed that
1533 # the Federal District will not adopt DST.
1534 # * 4 of 16 district leaders announced they'll ignore the decree.
1535 # * The decree does not affect federal-controlled facilities including
1536 # the airport, banks, hospitals, and schools.
1538 # For now we'll assume that the Federal District will bow to federal rules.
1540 # From Jesper Norgaard (2001-04-01):
1541 # I found some references to the Mexican application of daylight
1542 # saving, which modifies what I had already sent you, stating earlier
1543 # that a number of northern Mexican states would go on daylight
1544 # saving. The modification reverts this to only cover Baja California
1545 # (Norte), while all other states (except Sonora, who has no daylight
1546 # saving all year) will follow the original decree of president
1547 # Vicente Fox, starting daylight saving May 6, 2001 and ending
1548 # September 30, 2001.
1549 # References: "Diario de Monterrey" <www.diariodemonterrey.com/index.asp>
1550 # Palabra <http://palabra.infosel.com/010331/primera/ppri3101.pdf> (2001-03-31)
1552 # From Reuters (2001-09-04):
1553 # Mexico's Supreme Court on Tuesday declared that daylight savings was
1554 # unconstitutional in Mexico City, creating the possibility the
1555 # capital will be in a different time zone from the rest of the nation
1556 # next year.... The Supreme Court's ruling takes effect at 2:00
1557 # a.m. (0800 GMT) on Sept. 30, when Mexico is scheduled to revert to
1558 # standard time. "This is so residents of the Federal District are not
1559 # subject to unexpected time changes," a statement from the court said.
1561 # From Jesper Norgaard Welen (2002-03-12):
1562 # ... consulting my local grocery store(!) and my coworkers, they all insisted
1563 # that a new decision had been made to reinstate US style DST in Mexico....
1564 # http://www.conae.gob.mx/ahorro/horaver2001_m1_2002.html (2002-02-20)
1565 # confirms this. Sonora as usual is the only state where DST is not applied.
1567 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1568 Rule Mexico 1939 only - Feb 5 0:00 1:00 D
1569 Rule Mexico 1939 only - Jun 25 0:00 0 S
1570 Rule Mexico 1940 only - Dec 9 0:00 1:00 D
1571 Rule Mexico 1941 only - Apr 1 0:00 0 S
1572 Rule Mexico 1943 only - Dec 16 0:00 1:00 W # War
1573 Rule Mexico 1944 only - May 1 0:00 0 S
1574 Rule Mexico 1950 only - Feb 12 0:00 1:00 D
1575 Rule Mexico 1950 only - Jul 30 0:00 0 S
1576 Rule Mexico 1996 2000 - Apr Sun>=1 2:00 1:00 D
1577 Rule Mexico 1996 2000 - Oct lastSun 2:00 0 S
1578 Rule Mexico 2001 only - May Sun>=1 2:00 1:00 D
1579 Rule Mexico 2001 only - Sep lastSun 2:00 0 S
1580 Rule Mexico 2002 max - Apr Sun>=1 2:00 1:00 D
1581 Rule Mexico 2002 max - Oct lastSun 2:00 0 S
1582 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1584 Zone America/Cancun -5:47:04 - LMT 1922 Jan 1 0:12:56
1585 -6:00 - CST 1981 Dec 23
1586 -5:00 Mexico E%sT 1998 Aug 2 2:00
1589 Zone America/Merida -5:58:28 - LMT 1922 Jan 1 0:01:32
1590 -6:00 - CST 1981 Dec 23
1591 -5:00 - EST 1982 Dec 2
1593 # Coahuila, Durango, Nuevo Leon, Tamaulipas
1594 Zone America/Monterrey -6:41:16 - LMT 1921 Dec 31 23:18:44
1599 Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 0:23:24
1600 -7:00 - MST 1927 Jun 10 23:00
1601 -6:00 - CST 1930 Nov 15
1602 -7:00 - MST 1931 May 1 23:00
1603 -6:00 - CST 1931 Oct
1604 -7:00 - MST 1932 Apr 1
1605 -6:00 Mexico C%sT 2001 Sep 30 02:00
1606 -6:00 - CST 2002 Feb 20
1609 Zone America/Chihuahua -7:04:20 - LMT 1921 Dec 31 23:55:40
1610 -7:00 - MST 1927 Jun 10 23:00
1611 -6:00 - CST 1930 Nov 15
1612 -7:00 - MST 1931 May 1 23:00
1613 -6:00 - CST 1931 Oct
1614 -7:00 - MST 1932 Apr 1
1616 -6:00 Mexico C%sT 1998
1617 -6:00 - CST 1998 Apr Sun>=1 3:00
1620 Zone America/Hermosillo -7:23:52 - LMT 1921 Dec 31 23:36:08
1621 -7:00 - MST 1927 Jun 10 23:00
1622 -6:00 - CST 1930 Nov 15
1623 -7:00 - MST 1931 May 1 23:00
1624 -6:00 - CST 1931 Oct
1625 -7:00 - MST 1932 Apr 1
1626 -6:00 - CST 1942 Apr 24
1627 -7:00 - MST 1949 Jan 14
1629 -7:00 Mexico M%sT 1999
1631 # Baja California Sur, Nayarit, Sinaloa
1632 Zone America/Mazatlan -7:05:40 - LMT 1921 Dec 31 23:54:20
1633 -7:00 - MST 1927 Jun 10 23:00
1634 -6:00 - CST 1930 Nov 15
1635 -7:00 - MST 1931 May 1 23:00
1636 -6:00 - CST 1931 Oct
1637 -7:00 - MST 1932 Apr 1
1638 -6:00 - CST 1942 Apr 24
1639 -7:00 - MST 1949 Jan 14
1643 Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 0:11:56
1645 -8:00 - PST 1927 Jun 10 23:00
1646 -7:00 - MST 1930 Nov 15
1647 -8:00 - PST 1931 Apr 1
1648 -8:00 1:00 PDT 1931 Sep 30
1649 -8:00 - PST 1942 Apr 24
1650 -8:00 1:00 PWT 1945 Nov 12
1651 -8:00 - PST 1948 Apr 5
1652 -8:00 1:00 PDT 1949 Jan 14
1657 -8:00 Mexico P%sT 2001
1658 -8:00 US P%sT 2002 Feb 20
1660 # From Paul Eggert (2001-03-05):
1661 # Formerly there was an America/Ensenada zone, which differed from
1662 # America/Tijuana only in that it did not observe DST from 1976
1663 # through 1995. This was as per Shanks. However, Guy Harris reports
1664 # that the 1987 OAG says "Only Ensenada, Mexicale, San Felipe and
1665 # Tijuana observe DST," which contradicts Shanks but does imply that
1666 # DST-observance was a town-by-town matter back then. This concerns
1667 # data after 1970 so most likely there should be at least one Zone
1668 # other than America/Tijuana for Baja, but it's not clear yet what its
1669 # name or contents should be.
1674 ###############################################################################
1677 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1678 Zone America/Anguilla -4:12:16 - LMT 1912 Mar 2
1681 # Antigua and Barbuda
1682 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1683 Zone America/Antigua -4:07:12 - LMT 1912 Mar 2
1688 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1689 Rule Bahamas 1964 max - Oct lastSun 2:00 0 S
1690 Rule Bahamas 1964 1986 - Apr lastSun 2:00 1:00 D
1691 Rule Bahamas 1987 max - Apr Sun>=1 2:00 1:00 D
1692 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1693 Zone America/Nassau -5:09:24 - LMT 1912 Mar 2
1697 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1698 Rule Barb 1977 only - Jun 12 2:00 1:00 D
1699 Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S
1700 Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D
1701 Rule Barb 1979 only - Sep 30 2:00 0 S
1702 Rule Barb 1980 only - Sep 25 2:00 0 S
1703 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1704 Zone America/Barbados -3:58:28 - LMT 1924 # Bridgetown
1705 -3:58:28 - BMT 1932 # Bridgetown Mean Time
1709 # Whitman entirely disagrees with Shanks; go with Shanks.
1710 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1711 Rule Belize 1918 1942 - Oct Sun>=2 0:00 0:30 HD
1712 Rule Belize 1919 1943 - Feb Sun>=9 0:00 0 S
1713 Rule Belize 1973 only - Dec 5 0:00 1:00 D
1714 Rule Belize 1974 only - Feb 9 0:00 0 S
1715 Rule Belize 1982 only - Dec 18 0:00 1:00 D
1716 Rule Belize 1983 only - Feb 12 0:00 0 S
1717 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1718 Zone America/Belize -5:52:48 - LMT 1912 Apr
1722 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1723 Zone Atlantic/Bermuda -4:19:04 - LMT 1930 Jan 1 2:00 # Hamilton
1724 -4:00 - AST 1974 Apr 28 2:00
1728 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1729 Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown
1730 -5:07:12 - KMT 1912 Feb # Kingston Mean Time
1734 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1735 Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D
1736 Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S
1737 Rule CR 1991 1992 - Jan Sat>=15 0:00 1:00 D
1738 # IATA SSIM (1991-09) says the following was at 1:00; go with Shanks.
1739 Rule CR 1991 only - Jul 1 0:00 0 S
1740 Rule CR 1992 only - Mar 15 0:00 0 S
1741 # There are too many San Joses elsewhere, so we'll use `Costa Rica'.
1742 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1743 Zone America/Costa_Rica -5:36:20 - LMT 1890 # San Jose
1744 -5:36:20 - SJMT 1921 Jan 15 # San Jose Mean Time
1747 # no information; probably like America/Costa_Rica
1751 # From Arthur David Olson (1999-03-29):
1752 # The 1999-03-28 exhibition baseball game held in Havana, Cuba, between
1753 # the Cuban National Team and the Baltimore Orioles was carried live on
1754 # the Orioles Radio Network, including affiliate WTOP in Washington, DC.
1755 # During the game, play-by-play announcer Jim Hunter noted that
1756 # "We'll be losing two hours of sleep...Cuba switched to Daylight Saving
1757 # Time today." (The "two hour" remark referred to losing one hour of
1758 # sleep on 1999-03-28--when the announcers were in Cuba as it switched
1759 # to DST--and one more hour on 1999-04-04--when the announcers will have
1760 # returned to Baltimore, which switches on that date.)
1762 # From Evert van der Veer via Steffen Thorsen (2004-10-28):
1763 # Cuba is not going back to standard time this year.
1764 # From Paul Eggert (2004-10-28):
1765 # http://www.granma.cu/ingles/2004/septiembre/juev30/41medid-i.html
1766 # says that it's due to a problem at the Antonio Guiteras
1767 # thermoelectric plant, and says "This October there will be no return
1768 # to normal hours (after daylight saving time)".
1769 # For now, let's assume that it's a one-year temporary measure.
1771 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1772 Rule Cuba 1928 only - Jun 10 0:00 1:00 D
1773 Rule Cuba 1928 only - Oct 10 0:00 0 S
1774 Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D
1775 Rule Cuba 1940 1942 - Sep Sun>=1 0:00 0 S
1776 Rule Cuba 1945 1946 - Jun Sun>=1 0:00 1:00 D
1777 Rule Cuba 1945 1946 - Sep Sun>=1 0:00 0 S
1778 Rule Cuba 1965 only - Jun 1 0:00 1:00 D
1779 Rule Cuba 1965 only - Sep 30 0:00 0 S
1780 Rule Cuba 1966 only - May 29 0:00 1:00 D
1781 Rule Cuba 1966 only - Oct 2 0:00 0 S
1782 Rule Cuba 1967 only - Apr 8 0:00 1:00 D
1783 Rule Cuba 1967 1968 - Sep Sun>=8 0:00 0 S
1784 Rule Cuba 1968 only - Apr 14 0:00 1:00 D
1785 Rule Cuba 1969 1977 - Apr lastSun 0:00 1:00 D
1786 Rule Cuba 1969 1971 - Oct lastSun 0:00 0 S
1787 Rule Cuba 1972 1974 - Oct 8 0:00 0 S
1788 Rule Cuba 1975 1977 - Oct lastSun 0:00 0 S
1789 Rule Cuba 1978 only - May 7 0:00 1:00 D
1790 Rule Cuba 1978 1990 - Oct Sun>=8 0:00 0 S
1791 Rule Cuba 1979 1980 - Mar Sun>=15 0:00 1:00 D
1792 Rule Cuba 1981 1985 - May Sun>=5 0:00 1:00 D
1793 Rule Cuba 1986 1989 - Mar Sun>=14 0:00 1:00 D
1794 Rule Cuba 1990 1997 - Apr Sun>=1 0:00 1:00 D
1795 Rule Cuba 1991 1995 - Oct Sun>=8 0:00s 0 S
1796 Rule Cuba 1996 only - Oct 6 0:00s 0 S
1797 Rule Cuba 1997 only - Oct 12 0:00s 0 S
1798 Rule Cuba 1998 1999 - Mar lastSun 0:00s 1:00 D
1799 Rule Cuba 1998 2003 - Oct lastSun 0:00s 0 S
1800 Rule Cuba 2000 max - Apr Sun>=1 0:00s 1:00 D
1801 Rule Cuba 2005 max - Oct lastSun 0:00s 0 S
1803 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1804 Zone America/Havana -5:29:28 - LMT 1890
1805 -5:29:36 - HMT 1925 Jul 19 12:00 # Havana MT
1809 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1810 Zone America/Dominica -4:05:36 - LMT 1911 Jul 1 0:01 # Roseau
1813 # Dominican Republic
1815 # From Steffen Thorsen (2000-10-30):
1816 # Enrique Morales reported to me that the Dominican Republic has changed the
1817 # time zone to Eastern Standard Time as of Sunday 29 at 2 am....
1818 # http://www.listin.com.do/antes/261000/republica/princi.html
1820 # From Paul Eggert (2000-12-04):
1821 # That URL (2000-10-26, in Spanish) says they planned to use US-style DST.
1823 # From Rives McDow (2000-12-01):
1824 # Dominican Republic changed its mind and presidential decree on Tuesday,
1825 # November 28, 2000, with a new decree. On Sunday, December 3 at 1:00 AM the
1826 # Dominican Republic will be reverting to 8 hours from the International Date
1827 # Line, and will not be using DST in the foreseeable future. The reason they
1828 # decided to use DST was to be in synch with Puerto Rico, who was also going
1829 # to implement DST. When Puerto Rico didn't implement DST, the president
1830 # decided to revert.
1833 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1834 Rule DR 1966 only - Oct 30 0:00 1:00 D
1835 Rule DR 1967 only - Feb 28 0:00 0 S
1836 Rule DR 1969 1973 - Oct lastSun 0:00 0:30 HD
1837 Rule DR 1970 only - Feb 21 0:00 0 S
1838 Rule DR 1971 only - Jan 20 0:00 0 S
1839 Rule DR 1972 1974 - Jan 21 0:00 0 S
1840 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1841 Zone America/Santo_Domingo -4:39:36 - LMT 1890
1842 -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT
1843 -5:00 DR E%sT 1974 Oct 27
1844 -4:00 - AST 2000 Oct 29 02:00
1845 -5:00 US E%sT 2000 Dec 3 01:00
1849 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1850 Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D
1851 Rule Salv 1987 1988 - Sep lastSun 0:00 0 S
1852 # There are too many San Salvadors elsewhere, so use America/El_Salvador
1853 # instead of America/San_Salvador.
1854 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1855 Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador
1859 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1860 Zone America/Grenada -4:07:00 - LMT 1911 Jul # St George's
1864 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1865 Zone America/Guadeloupe -4:06:08 - LMT 1911 Jun 8 # Pointe a Pitre
1869 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1870 Rule Guat 1973 only - Nov 25 0:00 1:00 D
1871 Rule Guat 1974 only - Feb 24 0:00 0 S
1872 Rule Guat 1983 only - May 21 0:00 1:00 D
1873 Rule Guat 1983 only - Sep 22 0:00 0 S
1874 Rule Guat 1991 only - Mar 23 0:00 1:00 D
1875 Rule Guat 1991 only - Sep 7 0:00 0 S
1876 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1877 Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5
1881 # From Gwillim Law (2005-04-15):
1882 # Risto O. Nykanen wrote me that Haiti is now on DST.
1883 # I searched for confirmation, and I found a
1884 # <a href="http://www.haitianconsulate.org/time.doc"> press release
1885 # on the Web page of the Haitian Consulate in Chicago (2005-03-31),
1886 # </a>. Translated from French, it says:
1888 # "The Prime Minister's Communication Office notifies the public in general
1889 # and the press in particular that, following a decision of the Interior
1890 # Ministry and the Territorial Collectivities [I suppose that means the
1891 # provinces], Haiti will move to Eastern Daylight Time in the night from next
1892 # Saturday the 2nd to Sunday the 3rd.
1894 # "Consequently, the Prime Minister's Communication Office wishes to inform
1895 # the population that the country's clocks will be set forward one hour
1896 # starting at midnight. This provision will hold until the last Saturday in
1899 # "Port-au-Prince, March 31, 2005"
1901 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1902 Rule Haiti 1983 only - May 8 0:00 1:00 D
1903 Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D
1904 Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S
1905 # Shanks says AT is 2:00, but IATA SSIM (1991/1997) says 1:00s. Go with IATA.
1906 Rule Haiti 1988 1997 - Apr Sun>=1 1:00s 1:00 D
1907 Rule Haiti 1988 1997 - Oct lastSun 1:00s 0 S
1908 Rule Haiti 2005 only - Apr Sun>=1 0:00 1:00 D
1909 Rule Haiti 2005 only - Oct lastSun 0:00 0 S
1910 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1911 Zone America/Port-au-Prince -4:49:20 - LMT 1890
1912 -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT
1916 # Shanks says 1921 Jan 1; go with Whitman's more precise Apr 1.
1917 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1918 Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr
1921 # Great Swan I ceded by US to Honduras in 1972
1925 # From Bob Devine (1988-01-28):
1928 # From U. S. Naval Observatory (1989-01-19):
1929 # JAMAICA 5 H BEHIND UTC
1932 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1933 Zone America/Jamaica -5:07:12 - LMT 1890 # Kingston
1934 -5:07:12 - KMT 1912 Feb # Kingston Mean Time
1935 -5:00 - EST 1974 Apr 28 2:00
1940 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1941 Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France
1942 -4:04:20 - FFMT 1911 May # Fort-de-France MT
1943 -4:00 - AST 1980 Apr 6
1944 -4:00 1:00 ADT 1980 Sep 28
1948 # From Paul Eggert (1997-08-31):
1949 # Recent volcanic eruptions have forced evacuation of Plymouth, the capital.
1950 # Luckily, Olveston, the current de facto capital, has the same longitude.
1951 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1952 Zone America/Montserrat -4:08:52 - LMT 1911 Jul 1 0:01 # Olveston
1957 # From Steffen Thorsen (1998-12-29):
1958 # Nicaragua seems to be back at -6:00 but I have not been able to find when
1959 # they changed from -5:00.
1961 # From Steffen Thorsen (2005-04-12):
1962 # I've got reports from 8 different people that Nicaragua just started
1963 # DST on Sunday 2005-04-10, in order to save energy because of
1964 # expensive petroleum. The exact end date for DST is not yet
1965 # announced, only "September" but some sites also say "mid-September".
1966 # Some background information is available on the President's official site:
1967 # http://www.presidencia.gob.ni/Presidencia/Files_index/Secretaria/Notas%20de%20Prensa/Presidente/2005/ABRIL/Gobierno-de-nicaragua-adelanta-hora-oficial-06abril.htm
1968 # The Decree, no 23-2005 is available here:
1969 # 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
1971 # From Paul Eggert (2005-04-12):
1972 # The decree doesn't say anything about daylight saving, but for now let's
1973 # assume that it is daylight saving and that they'll switch back on the
1974 # 2nd Sunday in September.
1976 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1977 Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D
1978 Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S
1979 Rule Nic 1992 only - Jan 1 4:00 1:00 D
1980 Rule Nic 1992 only - Sep 24 0:00 0 S
1981 Rule Nic 2005 only - Apr 10 0:00 1:00 D
1982 Rule Nic 2005 only - Sep 11 0:00 0 S
1983 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1984 Zone America/Managua -5:45:08 - LMT 1890
1985 -5:45:12 - MMT 1934 Jun 23 # Managua Mean Time?
1986 -6:00 - CST 1973 May
1987 -5:00 - EST 1975 Feb 16
1988 -6:00 Nic C%sT 1993 Jan 1 4:00
1989 -5:00 - EST 1998 Dec
1993 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1994 Zone America/Panama -5:18:08 - LMT 1890
1995 -5:19:36 - CMT 1908 Apr 22 # Colon Mean Time
1999 # There are too many San Juans elsewhere, so we'll use `Puerto_Rico'.
2000 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2001 Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan
2002 -4:00 - AST 1942 May 3
2003 -4:00 1:00 AWT 1945 Sep 30 2:00
2007 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2008 Zone America/St_Kitts -4:10:52 - LMT 1912 Mar 2 # Basseterre
2012 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2013 Zone America/St_Lucia -4:04:00 - LMT 1890 # Castries
2014 -4:04:00 - CMT 1912 # Castries Mean Time
2017 # St Pierre and Miquelon
2018 # There are too many St Pierres elsewhere, so we'll use `Miquelon'.
2019 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2020 Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre
2021 -4:00 - AST 1980 May
2022 -3:00 - PMST 1987 # Pierre & Miquelon Time
2025 # St Vincent and the Grenadines
2026 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2027 Zone America/St_Vincent -4:04:56 - LMT 1890 # Kingstown
2028 -4:04:56 - KMT 1912 # Kingstown Mean Time
2032 # From Paul Eggert (1998-08-06):
2033 # Shanks says they use US DST rules, but IATA SSIM (1991/1998)
2034 # says they switch at midnight. Go with IATA SSIM.
2035 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
2036 Rule TC 1979 1986 - Apr lastSun 0:00 1:00 D
2037 Rule TC 1979 max - Oct lastSun 0:00 0 S
2038 Rule TC 1987 max - Apr Sun>=1 0:00 1:00 D
2039 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2040 Zone America/Grand_Turk -4:44:32 - LMT 1890
2041 -5:07:12 - KMT 1912 Feb # Kingston Mean Time
2045 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2046 Zone America/Tortola -4:18:28 - LMT 1911 Jul # Road Town
2050 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
2051 Zone America/St_Thomas -4:19:44 - LMT 1911 Jul # Charlotte Amalie
projects / dragonfly.git / blob