1 # @(#)northamerica 7.35
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 <eggert@twinsun.com> (1994-08-17):
9 # A reliable and entertaining source about time zones is
10 # Derek Howse, Greenwich time and the discovery of the longitude,
11 # Oxford University Press (1980).
13 ###############################################################################
17 # From Paul Eggert <eggert@twinsun.com> (1995-12-19):
18 # A good source for time zone historical data in the US is
19 # Thomas G. Shanks, The American Atlas (5th edition),
20 # San Diego: ACS Publications, Inc. (1991).
21 # Make sure you have the errata sheet; the book is somewhat useless without it.
22 # It is the source for the US and Puerto Rico entries below.
24 # From Paul Eggert (1996-06-12):
25 # Daylight Saving Time was first suggested as a joke by Benjamin Franklin
26 # in his whimsical essay ``Turkey vs Eagle, McCauley is my Beagle'' (1784).
27 # Not everyone is happy with the results:
29 # I don't really care how time is reckoned so long as there is some
30 # agreement about it, but I object to being told that I am saving
31 # daylight when my reason tells me that I am doing nothing of the kind.
32 # I even object to the implication that I am wasting something
33 # valuable if I stay in bed after the sun has risen. As an admirer
34 # of moonlight I resent the bossy insistence of those who want to
35 # reduce my time for enjoying it. At the back of the Daylight Saving
36 # scheme I detect the bony, blue-fingered hand of Puritanism, eager
37 # to push people into bed earlier, and get them up earlier, to make
38 # them healthy, wealthy and wise in spite of themselves.
40 # -- Robertson Davies, The Diary of Samuel Marchbanks (1947), XIX, Sunday
42 # From Arthur David Olson:
43 # US Daylight Saving Time ended on the last Sunday of *October* in 1974.
44 # See, for example, the front page of the Saturday, 1974-10-26
45 # and Sunday, 1974-10-27 editions of the Washington Post.
47 # From Arthur David Olson:
48 # Before the Uniform Time Act of 1966 took effect in 1967, observance of
49 # Daylight Saving Time in the US was by local option, except during wartime.
51 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
52 Rule US 1918 1919 - Mar lastSun 2:00 1:00 W # War
53 Rule US 1918 1919 - Oct lastSun 2:00 0 S
54 Rule US 1942 only - Feb 9 2:00 1:00 W # War
55 Rule US 1945 only - Sep 30 2:00 0 S
56 Rule US 1967 max - Oct lastSun 2:00 0 S
57 Rule US 1967 1973 - Apr lastSun 2:00 1:00 D
58 Rule US 1974 only - Jan 6 2:00 1:00 D
59 Rule US 1975 only - Feb 23 2:00 1:00 D
60 Rule US 1976 1986 - Apr lastSun 2:00 1:00 D
61 Rule US 1987 max - Apr Sun>=1 2:00 1:00 D
63 # From Bob Devine (1988-01-28):
64 # ...Alaska (and Hawaii) had the timezone names changed in 1967.
66 # Pacific Standard Time(PST) -same-
67 # Yukon Standard Time(YST) -same-
68 # Central Alaska S.T. (CAT) Alaska-Hawaii St[an]dard Time (AHST)
69 # Nome Standard Time (NT) Bering Standard Time (BST)
71 # ...Alaska's timezone lines were redrawn in 1983 to give only 2 tz.
72 # The YST zone now covers nearly all of the state, AHST just part
73 # of the Aleutian islands. No DST.
75 # From Paul Eggert (1995-12-19):
76 # The tables below use `NST', not `NT', for Nome Standard Time.
77 # I invented `CAWT' for Central Alaska War Time.
79 # From U. S. Naval Observatory (1989-01-19):
80 # USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON
81 # USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30
82 # USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON
83 # USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30
84 # USA MOUNTAIN 7 H BEHIND UTC DENVER
85 # USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30
86 # USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO
87 # USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30
88 # USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST)
89 # USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT)
90 # USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W
91 # USA - " - 9 H BEHIND UTC APR 3 - OCT 30
92 # USA HAWAII 10 H BEHIND UTC
93 # USA BERING 11 H BEHIND UTC SAMOA, MIDWAY
95 # From Arthur David Olson (1989-01-21):
96 # The above dates are for 1988.
97 # Note the "AKST" and "AKDT" abbreviations, the claim that there's
98 # no DST in Samoa, and the claim that there is DST in Alaska and the
101 # From Arthur David Olson (1988-02-13):
102 # Legal standard time zone names, from United States Code (1982 Edition and
103 # Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names
104 # up to 1967-04-01 (when most provisions of the Uniform Time Act of 1966
105 # took effect), as explained in sections 263 and 261:
107 # United States standard eastern time
108 # United States standard mountain time
109 # United States standard central time
110 # United States standard Pacific time
112 # United States standard Alaska time
114 # Next, names from 1967-04-01 until 1983-11-30 (the date for
115 # public law 98-181):
116 # Atlantic standard time
117 # eastern standard time
118 # central standard time
119 # mountain standard time
120 # Pacific standard time
121 # Yukon standard time
122 # Alaska-Hawaii standard time
123 # Bering standard time
124 # And after 1983-11-30:
125 # Atlantic standard time
126 # eastern standard time
127 # central standard time
128 # mountain standard time
129 # Pacific standard time
130 # Alaska standard time
131 # Hawaii-Aleutian standard time
132 # Samoa standard time
133 # The law doesn't give abbreviations.
135 # From Paul Eggert (1995-12-19):
136 # Shanks uses 1983-10-30, not 1983-11-30, for the 1983 transitions.
139 # US Eastern time, represented by New York
140 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
141 Rule NYC 1920 only - Mar lastSun 2:00 1:00 D
142 Rule NYC 1920 only - Oct lastSun 2:00 0 S
143 Rule NYC 1921 1966 - Apr lastSun 2:00 1:00 D
144 Rule NYC 1921 1954 - Sep lastSun 2:00 0 S
145 Rule NYC 1955 1966 - Oct lastSun 2:00 0 S
146 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
147 Zone America/New_York -4:56:02 - LMT 1883 Nov 18 12:00
154 # US Central time, represented by Chicago
155 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
156 Rule Chicago 1920 only - Jun 13 2:00 1:00 D
157 Rule Chicago 1920 1921 - Oct lastSun 2:00 0 S
158 Rule Chicago 1921 only - Mar lastSun 2:00 1:00 D
159 Rule Chicago 1922 1966 - Apr lastSun 2:00 1:00 D
160 Rule Chicago 1922 1954 - Sep lastSun 2:00 0 S
161 Rule Chicago 1955 1966 - Oct lastSun 2:00 0 S
162 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
163 Zone America/Chicago -5:50:36 - LMT 1883 Nov 18 12:00
165 -6:00 Chicago C%sT 1936 Mar 1 2:00
166 -5:00 - EST 1936 Nov 15 2:00
167 -6:00 Chicago C%sT 1942
169 -6:00 Chicago C%sT 1967
172 # US Mountain time, represented by Denver
173 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
174 Rule Denver 1920 1921 - Mar lastSun 2:00 1:00 D
175 Rule Denver 1920 only - Oct lastSun 2:00 0 S
176 Rule Denver 1921 only - May 22 2:00 0 S
177 Rule Denver 1965 1966 - Apr lastSun 2:00 1:00 D
178 Rule Denver 1965 1966 - Oct lastSun 2:00 0 S
179 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
180 Zone America/Denver -6:59:56 - LMT 1883 Nov 18 12:00
182 -7:00 Denver M%sT 1942
184 -7:00 Denver M%sT 1967
187 # US Pacific time, represented by Los Angeles
188 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
189 Rule CA 1948 only - Mar 14 2:00 1:00 D
190 Rule CA 1949 only - Jan 1 2:00 0 S
191 Rule CA 1950 1966 - Apr lastSun 2:00 1:00 D
192 Rule CA 1950 1961 - Sep lastSun 2:00 0 S
193 Rule CA 1962 1966 - Oct lastSun 2:00 0 S
194 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
195 Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 12:00
201 # AK%sT is the modern abbreviation for -9:00 per USNO.
203 # From Paul Eggert (1995-12-19):
204 # Howse writes that Alaska switched from the Julian to the Gregorian calendar,
205 # and from east-of-GMT to west-of-GMT days, when the US bought it from Russia.
206 # This was on 1867-10-18. We omit this transition, since we can't represent
207 # changes from Julian to Gregorian.
209 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
210 Zone America/Juneau -8:57:41 - LMT 1900 Aug 20 12:00
214 -8:00 US P%sT 1983 Oct 30 2:00
216 Zone America/Yakutat -9:18:55 - LMT 1900 Aug 20 12:00
220 -9:00 US Y%sT 1983 Oct 30 2:00
222 Zone America/Anchorage -9:59:36 - LMT 1900 Aug 20 12:00
224 -10:00 US CAT/CAWT 1946
225 -10:00 - CAT 1967 Apr
227 -10:00 US AH%sT 1983 Oct 30 2:00
229 Zone America/Nome -11:01:38 - LMT 1900 Aug 20 12:00
232 -11:00 - NST 1967 Apr
234 -11:00 US B%sT 1983 Oct 30 2:00
236 Zone America/Adak -11:46:38 - LMT 1900 Aug 20 12:00
239 -11:00 - NST 1967 Apr
241 -11:00 US B%sT 1983 Oct 30 2:00
243 # Shanks writes that part of southwest Alaska (e.g. Aniak)
244 # switched from -11:00 to -10:00 on 1968-09-22 at 02:00,
245 # and another part (e.g. Akiak) made the same switch five weeks later.
246 # These switches don't quite make our 1970 cutoff.
250 # From Arthur David Olson:
251 # And then there's Hawaii.
252 # DST was observed for one day in 1933;
253 # standard time was changed by half an hour in 1947;
254 # it's always standard as of 1986.
257 # Shanks says the 1933 experiment lasted for three weeks. Go with Shanks.
259 Zone Pacific/Honolulu -10:31:26 - LMT 1900 Jan 1 12:00
260 -10:30 - HST 1933 Apr 30 2:00
261 -10:30 1:00 HDT 1933 May 21 2:00
262 -10:30 US H%sT 1947 Jun 8 2:00
265 Zone Pacific/Midway -11:49:28 - LMT 1901
266 -11:00 - NST 1967 Apr # N=Nome
267 -11:00 - BST 1983 Nov 30 # B=Bering
268 -11:00 - SST # S=Samoa
270 # Now we turn to US areas that have diverged from the consensus since 1970.
272 # Arizona mostly uses MST.
273 Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 12:00
274 -7:00 US M%sT 1944 Jan 1 00:01
275 -7:00 - MST 1944 Mar 17 00:01
276 -7:00 US M%sT 1944 Oct 1 00:01
280 # From Arthur David Olson (1988-02-13):
281 # A writer from the Inter Tribal Council of Arizona, Inc.,
282 # notes in private correspondence dated 12/28/87 that "Presently, only the
283 # Navajo Nation participates in the Daylight Saving Time policy, due to its
284 # large size and location in three states." (The "only" means that other
285 # tribal nations don't use DST.)
287 Link America/Denver America/Shiprock
289 # Southern Idaho and eastern Oregon switched four weeks late in 1974.
290 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
291 Zone America/Boise -7:44:49 - LMT 1883 Nov 18 12:00
292 -8:00 US P%sT 1923 May 13 2:00
294 -7:00 - MST 1974 Feb 3 2:00
299 # From Paul Eggert (1995-12-19):
300 # Indiana generally observes either EST all year, or CST/CDT,
301 # but areas near Cincinnati and Louisville use those cities' timekeeping
302 # and in 1969 and 1970 the whole state observed daylight time;
303 # and there are other exceptions as noted below.
304 # Shanks partitions Indiana into 345 regions, each with its own time history,
305 # and writes ``Even newspaper reports present contradictory information.''
306 # Fortunately, most of the complexity occurred before our cutoff date of 1970.
308 # Since 1970, EST-only Indiana has been like America/Indianapolis,
309 # with exceptions noted below for Crawford, Starke, and Switzerland counties.
310 # The parts of Indiana not listed below have been like America/Chicago,
311 # America/Louisville, or America/New_York.
313 # Other than Indianapolis, the Indiana place names are so nondescript
314 # that they would be ambiguous if we left them at the `America' level.
315 # So we reluctantly put them all in a subdirectory `America/Indiana'.
317 # Most of EST-only Indiana last observed DST in 1970.
318 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
319 Rule Indianapolis 1941 only - Jun 22 2:00 1:00 D
320 Rule Indianapolis 1941 1954 - Sep lastSun 2:00 0 S
321 Rule Indianapolis 1946 1954 - Apr lastSun 2:00 1:00 D
322 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
323 Zone America/Indianapolis -5:44:38 - LMT 1883 Nov 18 12:00
325 -6:00 Indianapolis C%sT 1942
327 -6:00 Indianapolis C%sT 1955 Apr 24 2:00
328 -5:00 - EST 1957 Sep 29 2:00
329 -6:00 - CST 1958 Apr 27 2:00
333 Link America/Indianapolis America/Indiana/Indianapolis
335 # Part of Crawford County, Indiana, last observed DST in 1975,
336 # and left its clocks alone in 1974.
337 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
338 Rule Marengo 1951 only - Apr lastSun 2:00 1:00 D
339 Rule Marengo 1951 only - Sep lastSun 2:00 0 S
340 Rule Marengo 1954 1960 - Apr lastSun 2:00 1:00 D
341 Rule Marengo 1954 1960 - Sep lastSun 2:00 0 S
342 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
343 Zone America/Indiana/Marengo -5:45:23 - LMT 1883 Nov 18 12:00
345 -6:00 Marengo C%sT 1961 Apr 30 2:00
347 -5:00 US E%sT 1974 Jan 6 2:00
348 -6:00 1:00 CDT 1974 Oct 27 2:00
352 # Starke County, Indiana
353 # From Arthur David Olson (1991-10-28):
354 # An article on page A3 of the Sunday, 1991-10-27 Washington Post
355 # notes that Starke County switched from Central time to Eastern time as of
357 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
358 Rule Starke 1947 1961 - Apr lastSun 2:00 1:00 D
359 Rule Starke 1947 1954 - Sep lastSun 2:00 0 S
360 Rule Starke 1955 1956 - Oct lastSun 2:00 0 S
361 Rule Starke 1957 1958 - Sep lastSun 2:00 0 S
362 Rule Starke 1959 1961 - Oct lastSun 2:00 0 S
363 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
364 Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 12:00
366 -6:00 Starke C%sT 1962 Apr 29 2:00
367 -5:00 - EST 1963 Oct 27 2:00
368 -6:00 US C%sT 1991 Oct 27 2:00
371 # Switzerland County, Indiana, last observed DST in 1972.
372 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
373 Zone America/Indiana/Vevay -5:40:16 - LMT 1883 Nov 18 12:00
374 -6:00 US C%sT 1954 Apr 25 2:00
379 # Part of Kentucky left its clocks alone in 1974.
380 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
381 Rule Louisville 1921 only - May 1 2:00 1:00 D
382 Rule Louisville 1921 only - Sep 1 2:00 0 S
383 Rule Louisville 1941 1961 - Apr lastSun 2:00 1:00 D
384 Rule Louisville 1941 only - Sep lastSun 2:00 0 S
385 Rule Louisville 1946 only - Jun 2 2:00 0 S
386 Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S
387 Rule Louisville 1956 1960 - Oct lastSun 2:00 0 S
388 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
389 Zone America/Louisville -5:43:02 - LMT 1883 Nov 18 12:00
391 -6:00 Louisville C%sT 1942
393 -6:00 Louisville C%sT 1961 Jul 23 2:00
395 -5:00 US E%sT 1974 Jan 6 2:00
396 -6:00 1:00 CDT 1974 Oct 27 2:00
401 # From Bob Devine (1988-01-28):
402 # Michigan didn't observe DST from 1968 to 1973.
404 # From Paul Eggert (1995-12-19):
405 # Shanks writes that Michigan started using standard time on 1885 Sep 18,
406 # but Howse (p 126) writes that Detroit kept
408 # local time until 1900 when the City Council decreed that clocks should
409 # be put back twenty-eight minutes to Central Standard Time. Half the
410 # city obeyed, half refused. After considerable debate, the decision
411 # was rescinded and the city reverted to Sun time. A derisive offer to
412 # erect a sundial in front of the city hall was referred to the
413 # Committee on Sewers. Then, in 1905, Central time was adopted
416 # This story is too entertaining to be false, so go with Howse over Shanks.
418 # Most of Michigan observed DST from 1973 on, but was a bit late in 1975.
419 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
420 Rule Detroit 1948 only - Apr lastSun 2:00 1:00 D
421 Rule Detroit 1948 only - Sep lastSun 2:00 0 S
422 Rule Detroit 1967 only - Jun 14 2:00 1:00 D
423 Rule Detroit 1967 only - Oct lastSun 2:00 0 S
424 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
425 Zone America/Detroit -5:32:11 - LMT 1905
426 -6:00 - CST 1915 May 15 2:00
429 -5:00 Detroit E%sT 1973
431 -5:00 - EST 1975 Apr 27 2:00
434 # The Michigan border with Wisconsin switched from EST to CST/CDT in 1973.
435 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
436 Rule Menominee 1946 only - Apr lastSun 2:00 1:00 D
437 Rule Menominee 1946 only - Sep lastSun 2:00 0 S
438 Rule Menominee 1966 only - Apr lastSun 2:00 1:00 D
439 Rule Menominee 1966 only - Oct lastSun 2:00 0 S
440 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
441 Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00
443 -6:00 Menominee C%sT 1969 Apr 27 2:00
444 -5:00 - EST 1973 Apr 29 2:00
451 # Old names, for S5 users
453 # Link LINK-FROM LINK-TO
454 Link America/New_York EST5EDT
455 Link America/Chicago CST6CDT
456 Link America/Denver MST7MDT
457 Link America/Los_Angeles PST8PDT
458 Link America/Indianapolis EST
459 Link America/Phoenix MST
460 Link Pacific/Honolulu HST
462 ################################################################################
465 # From Paul Eggert <eggert@twinsun.com> (1996-11-22):
466 # A good source for time zone historical data outside the US is
467 # Thomas G. Shanks, The International Atlas (3rd edition),
468 # San Diego: ACS Publications, Inc. (1991).
470 # Gwillim Law <LAW@encmail.encompass.com> writes that a good source
471 # for recent time zone data is the International Air Transport
472 # Association's Standard Schedules Information Manual (IATA SSIM),
473 # published semiannually. Law sent in several helpful summaries
474 # of the IATA's data after 1990.
476 # Except where otherwise noted, Shanks is the source for entries through 1990,
477 # and IATA SSIM is the source for entries after 1990.
479 # Another source occasionally used is Edward W. Whitman, World Time Differences,
480 # Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated), which
481 # I found in the UCLA library.
483 # See the `europe' file for Greenland.
487 # From Alain LaBont<e'> <ALB@immedia.ca> (1994-11-14):
488 # I post here the time zone abbreviations standardized in Canada
489 # for both English and French in the CAN/CSA-Z234.4-89 standard....
491 # UTC Standard time Daylight savings time
492 # offset French English French English
503 # HN: Heure Normale ST: Standard Time
504 # HA: Heure Avanc<e'>e DT: Daylight saving Time
506 # A: de l'Atlantique Atlantic
507 # C: du Centre Central
508 # E: de l'Est Eastern
511 # P: du Pacifique Pacific
516 # From Paul Eggert <eggert@twinsun.com> (1994-11-22):
517 # Alas, this sort of thing must be handled by localization software.
519 # The data for Canada are all from Shanks (1991).
522 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
523 Rule Canada 1918 only - Apr 14 2:00 1:00 D
524 Rule Canada 1918 only - Oct 31 2:00 0 S
525 Rule Canada 1942 only - Feb 9 2:00 1:00 D
526 Rule Canada 1945 only - Sep 30 2:00 0 S
527 Rule Canada 1974 1986 - Apr lastSun 2:00 1:00 D
528 Rule Canada 1974 max - Oct lastSun 2:00 0 S
529 Rule Canada 1987 max - Apr Sun>=1 2:00 1:00 D
532 # Newfoundland (except Labrador)
534 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
535 Rule StJohns 1917 1918 - Apr Sun>=8 2:00 1:00 D
536 Rule StJohns 1917 only - Sep 17 2:00 0 S
537 Rule StJohns 1918 only - Oct 31 2:00 0 S
538 # Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks.
539 Rule StJohns 1919 only - May 5 23:00 1:00 D
540 Rule StJohns 1919 only - Aug 12 23:00 0 S
541 # For 1931-1935 Whitman gives Apr same date; go with Shanks.
542 Rule StJohns 1920 1935 - May Sun>=1 23:00 1:00 D
543 Rule StJohns 1920 1935 - Oct lastSun 23:00 0 S
544 # For 1936-1941 Shanks gives May Mon>=9 and Oct Mon>=2; go with Whitman.
545 Rule StJohns 1936 1941 - May Sun>=8 0:00 1:00 D
546 Rule StJohns 1936 1941 - Oct Sun>=1 0:00 0 S
547 # Shanks gives 1942 May 11 - 1945 Sep 30; go with Whitman.
548 Rule StJohns 1942 only - Mar 1 0:00 1:00 D
549 Rule StJohns 1942 only - Dec 31 0:00 0 S
550 Rule StJohns 1943 only - May 30 0:00 1:00 D
551 Rule StJohns 1943 only - Sep 5 0:00 0 S
552 Rule StJohns 1944 only - Jul 10 0:00 1:00 D
553 Rule StJohns 1944 only - Sep 2 0:00 0 S
554 Rule StJohns 1945 only - Jan 1 0:00 1:00 D
555 Rule StJohns 1945 only - Oct 7 2:00 0 S
556 # For 1946-9 Whitman gives May 5,4,9,1 - Oct 1,5,3,2, and for 1950 he gives
557 # Apr 30 - Sep 24; go with Shanks.
558 Rule StJohns 1946 1950 - May Sun>=8 2:00 1:00 D
559 Rule StJohns 1946 1950 - Oct Sun>=2 2:00 0 S
560 Rule StJohns 1951 1986 - Apr lastSun 2:00 1:00 D
561 Rule StJohns 1951 1959 - Sep lastSun 2:00 0 S
562 Rule StJohns 1960 max - Oct lastSun 2:00 0 S
563 Rule StJohns 1987 only - Apr Sun>=1 2:00 1:00 D
564 Rule StJohns 1988 only - Apr Sun>=1 2:00 2:00 DD
565 Rule StJohns 1989 max - Apr Sun>=1 2:00 1:00 D
566 # St John's has an apostrophe, but Posix file names can't have apostrophes.
567 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
568 Zone America/St_Johns -3:30:52 - LMT 1884
569 -3:30:52 StJohns N%sT 1935 Mar 30
575 # The name `Happy Valley-Goose Bay' is too long; use `Goose Bay'.
576 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
577 Zone America/Goose_Bay -4:01:40 - LMT 1884 # Happy Valley-Goose Bay
578 -3:30:52 StJohns NST 1919
579 -3:30:52 - NST 1935 Mar 30
581 -3:30 StJohns N%sT 1966 Mar 15 2:00
585 # west Labrador, New Brunswick, Nova Scotia, Prince Edward I
587 # From Paul Eggert (1996-06-12):
588 # Shanks writes that since 1970 most of this region has been like Halifax.
589 # Many locales did not observe peacetime DST until 1972;
590 # Glace Bay, NS is the largest that we know of.
591 # Shanks also writes that Liverpool, NS was the only town in Canada to observe
592 # DST in 1971 but not 1970; for now we'll assume this is a typo.
594 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
595 Rule Halifax 1916 only - Apr 1 0:00 1:00 D
596 Rule Halifax 1916 only - Oct 1 0:00 0 S
597 Rule Halifax 1918 only - Apr 14 2:00 1:00 D
598 Rule Halifax 1918 only - Oct 31 2:00 0 S
599 Rule Halifax 1920 only - May 9 0:00 1:00 D
600 Rule Halifax 1920 only - Aug 29 0:00 0 S
601 Rule Halifax 1921 only - May 6 0:00 1:00 D
602 Rule Halifax 1921 1922 - Sep 5 0:00 0 S
603 Rule Halifax 1922 only - Apr 30 0:00 1:00 D
604 Rule Halifax 1923 1925 - May Sun>=1 0:00 1:00 D
605 Rule Halifax 1923 only - Sep 4 0:00 0 S
606 Rule Halifax 1924 only - Sep 15 0:00 0 S
607 Rule Halifax 1925 only - Sep 28 0:00 0 S
608 Rule Halifax 1926 only - May 16 0:00 1:00 D
609 Rule Halifax 1926 only - Sep 13 0:00 0 S
610 Rule Halifax 1927 only - May 1 0:00 1:00 D
611 Rule Halifax 1927 only - Sep 26 0:00 0 S
612 Rule Halifax 1928 1931 - May Sun>=8 0:00 1:00 D
613 Rule Halifax 1928 only - Sep 9 0:00 0 S
614 Rule Halifax 1929 only - Sep 3 0:00 0 S
615 Rule Halifax 1930 only - Sep 15 0:00 0 S
616 Rule Halifax 1931 1932 - Sep Mon>=24 0:00 0 S
617 Rule Halifax 1933 only - Apr 30 0:00 1:00 D
618 Rule Halifax 1933 only - Oct 2 0:00 0 S
619 Rule Halifax 1934 only - May 20 0:00 1:00 D
620 Rule Halifax 1934 only - Sep 16 0:00 0 S
621 Rule Halifax 1935 only - Jun 2 0:00 1:00 D
622 Rule Halifax 1935 only - Sep 30 0:00 0 S
623 Rule Halifax 1936 only - Jun 1 0:00 1:00 D
624 Rule Halifax 1936 only - Sep 14 0:00 0 S
625 Rule Halifax 1937 1938 - May Sun>=1 0:00 1:00 D
626 Rule Halifax 1937 1941 - Sep Mon>=24 0:00 0 S
627 Rule Halifax 1939 only - May 28 0:00 1:00 D
628 Rule Halifax 1940 1941 - May Sun>=1 0:00 1:00 D
629 Rule Halifax 1942 only - Feb 9 2:00 1:00 D
630 Rule Halifax 1945 1959 - Sep lastSun 2:00 0 S
631 Rule Halifax 1946 1959 - Apr lastSun 2:00 1:00 D
632 Rule Halifax 1962 1986 - Apr lastSun 2:00 1:00 D
633 Rule Halifax 1962 max - Oct lastSun 2:00 0 S
634 Rule Halifax 1987 max - Apr Sun>=1 2:00 1:00 D
635 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
636 Zone America/Halifax -4:14:24 - LMT 1902 Jun 15
638 Zone America/Glace_Bay -3:59:48 - LMT 1902 Jun 15
639 -4:00 Canada A%sT 1953
640 -4:00 Halifax A%sT 1954
647 # From Paul Eggert (1996-06-12):
648 # Shanks writes that since 1970 most of this region has been like Montreal.
649 # Thunder Bay skipped DST in 1973.
650 # Many smaller locales did not observe peacetime DST until 1974;
651 # Nipigon (EST) and Rainy River (CST) are the largest that we know of.
652 # Far west Ontario is like Winnipeg; far east Quebec is like Halifax.
654 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
655 Rule Mont 1917 only - Mar 25 2:00 1:00 D
656 Rule Mont 1917 only - Apr 24 0:00 0 S
657 Rule Mont 1918 only - Apr 14 2:00 1:00 D
658 Rule Mont 1918 only - Oct 31 2:00 0 S
659 Rule Mont 1919 only - Mar 31 2:30 1:00 D
660 Rule Mont 1919 only - Oct 25 2:30 0 S
661 Rule Mont 1920 only - May 2 2:30 1:00 D
662 Rule Mont 1920 only - Oct 3 2:30 0 S
663 Rule Mont 1921 only - May 1 2:00 1:00 D
664 Rule Mont 1921 only - Oct 2 2:30 0 S
665 Rule Mont 1922 only - Apr 30 2:00 1:00 D
666 Rule Mont 1922 only - Oct 1 2:30 0 S
667 Rule Mont 1924 only - May 17 2:00 1:00 D
668 Rule Mont 1924 1926 - Sep lastSun 2:30 0 S
669 Rule Mont 1925 1926 - May Sun>=1 2:00 1:00 D
670 Rule Mont 1927 only - May 1 0:00 1:00 D
671 Rule Mont 1927 1932 - Sep Sun>=25 0:00 0 S
672 Rule Mont 1928 1931 - Apr Sun>=25 0:00 1:00 D
673 Rule Mont 1932 only - May 1 0:00 1:00 D
674 Rule Mont 1933 1940 - Apr Sun>=24 0:00 1:00 D
675 Rule Mont 1933 only - Oct 1 0:00 0 S
676 Rule Mont 1934 1939 - Sep Sun>=24 0:00 0 S
677 Rule Mont 1945 1948 - Sep lastSun 2:00 0 S
678 Rule Mont 1946 1986 - Apr lastSun 2:00 1:00 D
679 Rule Mont 1949 1950 - Oct lastSun 2:00 0 S
680 Rule Mont 1951 1956 - Sep lastSun 2:00 0 S
681 Rule Mont 1957 max - Oct lastSun 2:00 0 S
682 Rule Mont 1987 max - Apr Sun>=1 2:00 1:00 D
683 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
684 Zone America/Montreal -4:54:16 - LMT 1884
686 Zone America/Thunder_Bay -5:57:00 - LMT 1895
687 -5:00 Canada E%sT 1970
691 Zone America/Nipigon -5:53:04 - LMT 1895
693 Zone America/Rainy_River -6:17:56 - LMT 1895
699 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
700 Rule Winn 1916 only - Apr 23 0:00 1:00 D
701 Rule Winn 1916 only - Sep 17 0:00 0 S
702 Rule Winn 1918 only - Apr 14 2:00 1:00 D
703 Rule Winn 1918 only - Oct 31 2:00 0 S
704 Rule Winn 1937 only - May 16 2:00 1:00 D
705 Rule Winn 1937 only - Sep 26 2:00 0 S
706 Rule Winn 1942 only - Feb 9 2:00 1:00 D
707 Rule Winn 1945 only - Sep lastSun 2:00 0 S
708 Rule Winn 1946 only - May 12 2:00 1:00 D
709 Rule Winn 1946 only - Oct 13 2:00 0 S
710 Rule Winn 1947 1949 - Apr lastSun 2:00 1:00 D
711 Rule Winn 1947 1949 - Sep lastSun 2:00 0 S
712 Rule Winn 1950 only - May 1 2:00 1:00 D
713 Rule Winn 1950 only - Sep 30 2:00 0 S
714 Rule Winn 1951 1960 - Apr lastSun 2:00 1:00 D
715 Rule Winn 1951 1958 - Sep lastSun 2:00 0 S
716 Rule Winn 1959 only - Oct lastSun 2:00 0 S
717 Rule Winn 1960 only - Sep lastSun 2:00 0 S
718 Rule Winn 1963 only - Apr lastSun 2:00 1:00 D
719 Rule Winn 1963 only - Sep 22 2:00 0 S
720 Rule Winn 1966 1986 - Apr lastSun 2:00 1:00 D
721 Rule Winn 1966 max - Oct lastSun 2:00 0 S
722 Rule Winn 1987 max - Apr Sun>=1 2:00 1:00 D
723 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
724 Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16
730 # From Paul Eggert (1996-06-12):
731 # Shanks writes that since 1970 most of this region has been like Regina.
732 # Some western towns (e.g. Swift Current) switched from MST/MDT to CST in 1972.
733 # Other western towns (e.g. Lloydminster) are like Edmonton.
735 # From W. Jones <jones@skdad.usask.ca> (1992-11-06):
736 # The. . .below is based on information I got from our law library, the
737 # provincial archives, and the provincial Community Services department.
738 # A precise history would require digging through newspaper archives, and
739 # since you didn't say what you wanted, I didn't bother.
741 # Saskatchewan is split by a time zone meridian (105W) and over the years
742 # the boundary became pretty ragged as communities near it reevaluated
743 # their affiliations in one direction or the other. In 1965 a provincial
744 # referendum favoured legislating common time practices.
746 # On 15 April 1966 the Time Act (c. T-14, Revised Statutes of
747 # Saskatchewan 1978) was proclaimed, and established that the eastern
748 # part of Saskatchewan would use CST year round, that districts in
749 # northwest Saskatchewan would by default follow CST but could opt to
750 # follow Mountain Time rules (thus 1 hour difference in the winter and
751 # zero in the summer), and that districts in southwest Saskatchewan would
752 # by default follow MT but could opt to follow CST.
754 # It took a few years for the dust to settle (I know one story of a town
755 # on one time zone having its school in another, such that a mom had to
756 # serve her family lunch in two shifts), but presently it seems that only
757 # a few towns on the border with Alberta (e.g. Lloydminster) follow MT
758 # rules any more; all other districts appear to have used CST year round
759 # since sometime in the 1960s.
761 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
762 Rule Regina 1918 only - Apr 14 2:00 1:00 D
763 Rule Regina 1918 only - Oct 31 2:00 0 S
764 Rule Regina 1930 1934 - May Sun>=1 0:00 1:00 D
765 Rule Regina 1930 1934 - Oct Sun>=1 0:00 0 S
766 Rule Regina 1937 1941 - Apr Sun>=8 0:00 1:00 D
767 Rule Regina 1937 only - Oct Sun>=8 0:00 0 S
768 Rule Regina 1938 only - Oct Sun>=1 0:00 0 S
769 Rule Regina 1939 1941 - Oct Sun>=8 0:00 0 S
770 Rule Regina 1942 only - Feb 9 2:00 1:00 D
771 Rule Regina 1945 only - Sep lastSun 2:00 0 S
772 Rule Regina 1946 only - Apr Sun>=8 2:00 1:00 D
773 Rule Regina 1946 only - Oct Sun>=8 2:00 0 S
774 Rule Regina 1947 1959 - Apr lastSun 2:00 1:00 D
775 Rule Regina 1947 1958 - Sep lastSun 2:00 0 S
776 Rule Regina 1959 only - Oct lastSun 2:00 0 S
778 Rule Swift 1957 only - Apr lastSun 2:00 1:00 D
779 Rule Swift 1957 only - Oct lastSun 2:00 0 S
780 Rule Swift 1959 1961 - Apr lastSun 2:00 1:00 D
781 Rule Swift 1959 only - Oct lastSun 2:00 0 S
782 Rule Swift 1960 1961 - Sep lastSun 2:00 0 S
783 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
784 Zone America/Regina -6:58:36 - LMT 1905 Sep
785 -7:00 Regina M%sT 1960 Apr lastSun 2:00
787 Zone America/Swift_Current -7:11:20 - LMT 1905 Sep
788 -7:00 Canada M%sT 1946 Apr lastSun 2:00
789 -7:00 Regina M%sT 1950
790 -7:00 Swift M%sT 1972 Apr lastSun 2:00
796 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
797 Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D
798 Rule Edm 1918 only - Oct 31 2:00 0 S
799 Rule Edm 1919 only - May 27 2:00 0 S
800 Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D
801 Rule Edm 1920 only - Oct lastSun 2:00 0 S
802 Rule Edm 1921 1923 - Sep lastSun 2:00 0 S
803 Rule Edm 1942 only - Feb 9 2:00 1:00 D
804 Rule Edm 1945 only - Sep lastSun 2:00 0 S
805 Rule Edm 1947 only - Apr lastSun 2:00 1:00 D
806 Rule Edm 1947 only - Sep lastSun 2:00 0 S
807 Rule Edm 1967 only - Apr lastSun 2:00 1:00 D
808 Rule Edm 1967 only - Oct lastSun 2:00 0 S
809 Rule Edm 1969 only - Apr lastSun 2:00 1:00 D
810 Rule Edm 1969 only - Oct lastSun 2:00 0 S
811 Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D
812 Rule Edm 1972 max - Oct lastSun 2:00 0 S
813 Rule Edm 1987 max - Apr Sun>=1 2:00 1:00 D
814 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
815 Zone America/Edmonton -7:33:52 - LMT 1906 Sep
821 # From Paul Eggert (1996-06-12):
822 # Shanks writes that since 1970 most of this region has been like Vancouver.
823 # Dawswon Creek uses MST. Much of east BC is like Edmonton.
825 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
826 Rule Vanc 1918 only - Apr 14 2:00 1:00 D
827 Rule Vanc 1918 only - Oct 31 2:00 0 S
828 Rule Vanc 1942 only - Feb 9 2:00 1:00 D
829 Rule Vanc 1945 only - Sep 30 2:00 0 S
830 Rule Vanc 1946 1986 - Apr lastSun 2:00 1:00 D
831 Rule Vanc 1946 only - Oct 13 2:00 0 S
832 Rule Vanc 1947 1961 - Sep lastSun 2:00 0 S
833 Rule Vanc 1962 max - Oct lastSun 2:00 0 S
834 Rule Vanc 1987 max - Apr Sun>=1 2:00 1:00 D
835 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
836 Zone America/Vancouver -8:12:28 - LMT 1884
838 Zone America/Dawson_Creek -8:00:56 - LMT 1884
839 -8:00 Canada P%sT 1947
840 -8:00 Vanc P%sT 1972 Aug 30 2:00
844 # Northwest Territories, Yukon
846 # From Paul Eggert (1996-10-07):
847 # Dawson switched to PST in 1973. Inuvik switched to MST in 1979.
848 # Shanks's table for Watson Lake is corrupted, so we have no data there.
849 # Mathew Englander <mathew@io.org> (1996-10-07) gives the following refs:
850 # * 1967. Paragraph 28(34)(g) of the Interpretation Act, S.C. 1967-68,
851 # c. 7 defines Yukon standard time as UTC-9. This is still valid;
852 # see Interpretation Act, R.S.C. 1985, c. I-21, s. 35(1).
853 # * C.O. 1973/214 switched Yukon to PST on 1973-10-28 00:00.
854 # * O.I.C. 1980/02 established DST.
855 # * O.I.C. 1987/056 changed DST to Apr firstSun 2:00 to Oct lastSun 2:00.
856 # Shanks says Yukon's 1973-10-28 switch was at 2:00; go with Englander.
858 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
859 Rule NT_YK 1918 only - Apr 14 2:00 1:00 D
860 Rule NT_YK 1918 only - Oct 27 2:00 0 S
861 Rule NT_YK 1919 only - May 25 2:00 1:00 D
862 Rule NT_YK 1919 only - Nov 1 0:00 0 S
863 Rule NT_YK 1942 only - Feb 9 2:00 1:00 D
864 Rule NT_YK 1945 only - Sep 30 2:00 0 S
865 Rule NT_YK 1965 only - Apr lastSun 0:00 2:00 DD
866 Rule NT_YK 1965 only - Oct lastSun 2:00 0 S
867 Rule NT_YK 1980 1986 - Apr lastSun 2:00 1:00 D
868 Rule NT_YK 1980 max - Oct lastSun 2:00 0 S
869 Rule NT_YK 1987 max - Apr Sun>=1 2:00 1:00 D
870 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
871 Zone America/Pangnirtung -4:22:56 - LMT 1884
873 Zone America/Iqaluit -4:33:52 - LMT 1884 # Frobisher Bay
875 Zone America/Rankin_Inlet -6:08:40 - LMT 1884
877 Zone America/Yellowknife -7:37:24 - LMT 1884
879 Zone America/Inuvik -8:54:00 - LMT 1884
880 -8:00 NT_YK P%sT 1979 Apr lastSun 2:00
882 Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20
883 -9:00 NT_YK Y%sT 1966 Jul 1 2:00
885 Zone America/Dawson -9:17:40 - LMT 1900 Aug 20
886 -9:00 NT_YK Y%sT 1973 Oct 28 0:00
890 ###############################################################################
895 # Rules are from the Official Airline Guide, Worldwide Edition, for 1987.
896 # Rules prior to 1987 are unknown.
897 # The comments in the OAG say "Only Ensenada, Mexicale, San Felipe and Tijuana
898 # observe DST." This is presumably Baja California Norte, above 28th parallel,
899 # as listed there; [there is also] "Baja California Sur and N. Pacific
900 # Coast (States of Sinaloa and Sonora)."
902 # From Bob Devine (1988-01-28):
903 # The Federal District (where Mexico City is) has observed [DST] several
904 # times but not recently.
906 # I don't where to drawn the line in the North Baja area. 28th latitude
907 # sounds good -- but it may be higher (how far [d]o radio stations from
908 # San Diego affect culture?).
910 # The dates of DST probably go back to 1981. The rules are the same as
911 # US's. This is going to be a headache for US presidential electi[o]n years!
913 # From Arthur David Olson (1988-02-13)
914 # Since the 1981 starting date is only "probable," we'll keep the 1987
915 # starting date below.
917 # From U. S. Naval Observatory (1989-01-19):
918 # MEXICO BAJA CAL N 7 H BEHIND UTC BAJA CALIFORNIA SUR AND
919 # MEXICO BAJA CAL N N. PACIFIC COAST (STATES
920 # MEXICO BAJA CAL N OF SINALOA AND SONORA)
921 # MEXICO BAJA CAL N 8 H BEHIND UTC ABOVE 28TH PARALLEL APR 3
922 # MEXICO BAJA CAL N - OCT 29
923 # MEXICO BAJA CAL N 7 H BEHIND UTC ABOVE 28TH PARALLEL APR 3
924 # MEXICO BAJA CAL N - 0CT 29
925 # MEXICO 6 H BEHIND UTC STATES OF DURANGO,
926 # MEXICO COAHUILA, NUEVO LEON,
928 # MEXICO 5 H BEHIND UTC STATES OF DURANGO,
929 # MEXICO COAHUILA, NUEVO LEON,
930 # MEXICO TAMAULIPAS APR 3 - OCT 29
931 # MEXICO 6 H BEHIND UTC GENERAL MEXICO, STATES OF
932 # MEXICO CAMPECHE, QUINTANA ROO AND
935 # From Arthur David Olson (1989-01-21):
936 # April 3 fell on a Sunday in 1988; October 29 fell on a Sunday in 1989. Ahem.
937 # USNO claims there should be four Mexican zones rather than three:
938 # a zone that's GMT-8 with DST; a zone that's always GMT-7;
939 # a zone that's GMT-6 with DST; and a zone that's always GMT-6.
941 # From Paul Eggert <eggert@twinsun.com> (1993-11-18):
942 # Shanks also says there are four zones, but disagrees about the fourth.
943 # Instead of GMT-6 with DST, he says there's GMT-8 without DST.
945 # From Alan Perry <alan.perry@eng.sun.com> (1996-02-15):
946 # A guy from our Mexico subsidiary finally found the Presidential Decree
947 # outlining the timezone changes in Mexico.
949 # ------------- Begin Forwarded Message -------------
951 # I finally got my hands on the Official Presidential Decree that sets up the
952 # rules for the DST changes. The rules are:
954 # 1. The country is divided in 3 timezones:
955 # - Baja California Norte (the Mexico/BajaNorte TZ)
956 # - Baja California Sur, Nayarit, Sinaloa and Sonora (the Mexico/BajaSur TZ)
957 # - The rest of the country (the Mexico/General TZ)
959 # 2. From the first Sunday in April at 2:00 AM to the last Sunday in October
960 # at 2:00 AM, the times in each zone are as follows:
965 # 3. The rest of the year, the times are as follows:
970 # The Decree was published in Mexico's Official Newspaper on January 4th.
972 # -------------- End Forwarded Message --------------
973 # From Paul Eggert (1996-06-12):
974 # For an English translation of the decree,
975 # see ``Diario Oficial: Time Zone Changeover'',
976 # <URL:http://mexico-travel.com/extra/timezone_eng.html> (1996-01-04).
978 # From Shanks (1991):
979 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
980 Rule Mexico 1939 only - Feb 5 0:00 1:00 D
981 Rule Mexico 1939 only - Jun 25 0:00 0 S
982 Rule Mexico 1940 only - Dec 9 0:00 1:00 D
983 Rule Mexico 1941 only - Apr 1 0:00 0 S
984 Rule Mexico 1943 only - Dec 16 0:00 1:00 D
985 Rule Mexico 1944 only - May 1 0:00 0 S
986 Rule Mexico 1950 only - Feb 12 0:00 1:00 D
987 Rule Mexico 1950 only - Jul 30 0:00 0 S
988 Rule Mexico 1996 max - Apr Sun>=1 2:00 1:00 D
989 Rule Mexico 1996 max - Oct lastSun 2:00 0 S
991 Rule BajaN 1950 1966 - Apr lastSun 2:00 1:00 D
992 Rule BajaN 1950 1961 - Sep lastSun 2:00 0 S
993 Rule BajaN 1961 1966 - Oct lastSun 2:00 0 S
994 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
995 Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 0:23:24
996 -7:00 - MST 1927 Jun 10 23:00
997 -6:00 - CST 1930 Nov 15
998 -7:00 - MST 1931 May 1 23:00
1000 -7:00 - MST 1932 Mar 30 23:00
1002 Zone America/Mazatlan -7:05:40 - LMT 1921 Dec 31 23:54:20
1003 -7:00 - MST 1927 Jun 10 23:00
1004 -6:00 - CST 1930 Nov 15
1005 -7:00 - MST 1931 May 1 23:00
1006 -6:00 - CST 1931 Oct
1007 -7:00 - MST 1932 Mar 30 23:00
1008 -6:00 - CST 1942 Apr
1009 -7:00 - MST 1949 Jan 14
1012 Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 0:11:56
1013 -8:00 - PST 1927 Jun 10 23:00
1014 -7:00 - MST 1930 Nov 16
1015 -8:00 - PST 1942 Apr
1016 -7:00 - MST 1949 Jan 14
1017 -8:00 BajaN P%sT 1967 Apr lastSun 2:00
1020 Zone America/Ensenada -7:46:28 - LMT 1922 Jan 1 0:13:32
1021 -8:00 - PST 1927 Jun 10 23:00
1022 -7:00 - MST 1930 Nov 16
1023 -8:00 - PST 1942 Apr
1024 -7:00 - MST 1949 Jan 14
1031 ###############################################################################
1034 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1035 Zone America/Anguilla -4:12:16 - LMT 1912 Mar 2
1038 # Antigua and Barbuda
1039 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1040 Zone America/Antigua -4:07:12 - LMT 1912 Mar 2
1045 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1046 Rule Bahamas 1964 max - Oct lastSun 2:00 0 S
1047 Rule Bahamas 1964 1986 - Apr lastSun 2:00 1:00 D
1048 Rule Bahamas 1987 max - Apr Sun>=1 2:00 1:00 D
1049 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1050 Zone America/Nassau -5:09:24 - LMT 1912 Mar 2
1054 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1055 Rule Barb 1977 only - Jun 12 2:00 1:00 D
1056 Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S
1057 Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D
1058 Rule Barb 1979 only - Sep 30 2:00 0 S
1059 Rule Barb 1980 only - Sep 25 2:00 0 S
1060 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1061 Zone America/Barbados -3:58:28 - LMT 1924 # Bridgetown
1062 -3:58 - BMT 1932 # Bridgetown Mean Time
1066 # Whitman entirely disagrees with Shanks; go with Shanks.
1067 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1068 Rule Belize 1918 1942 - Oct Sun>=2 0:00 0:30 HD
1069 Rule Belize 1919 1943 - Feb Sun>=9 0:00 0 S
1070 Rule Belize 1973 only - Dec 5 0:00 1:00 D
1071 Rule Belize 1974 only - Feb 9 0:00 0 S
1072 Rule Belize 1982 only - Dec 18 0:00 1:00 D
1073 Rule Belize 1983 only - Feb 12 0:00 0 S
1074 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1075 Zone America/Belize -5:52:48 - LMT 1912 Apr
1079 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1080 Zone Atlantic/Bermuda -4:19:04 - LMT 1930 Jan 1 2:00 # Hamilton
1081 -4:00 - AST 1974 Apr 28 2:00
1085 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1086 Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown
1087 -5:07 - KMT 1912 Feb # Kingston Mean Time
1094 # Shanks gives some very odd dates for 1991, and stops there.
1095 # For now, we won't guess further.
1096 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1097 Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D
1098 Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S
1099 Rule CR 1991 1992 - Jan Sat>=15 0:00 1:00 D
1100 # IATA SSIM (1991-09) says the following was at 1:00; go with Shanks.
1101 Rule CR 1991 only - Jul 1 0:00 0 S
1102 Rule CR 1992 only - Mar 15 0:00 0 S
1103 # There are too many San Joses elsewhere, so we'll use `Costa Rica'.
1104 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1105 Zone America/Costa_Rica -5:36:20 - LMT 1890 # San Jose
1106 -5:36 - SJMT 1921 Jan 15 # San Jose Mean Time
1109 # no information; probably like America/Costa_Rica
1113 # From Bob Devine (1988-01-28):
1114 # . . .DST is from 2nd Sunday in May to 2nd Sunday in October since 1981.
1115 # Change at midnight. In 1979 & 1980, started at 3rd Sunday in March
1118 # From U. S. Naval Observatory (1989-01-19):
1119 # CUBA 5 H BEHIND UTC
1120 # CUBA 4 H BEHIND UTC MAR 20 - OCT 8
1122 # From Shanks (1991):
1123 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1124 Rule Cuba 1928 only - Jun 10 0:00 1:00 D
1125 Rule Cuba 1928 only - Oct 10 0:00 0 S
1126 Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D
1127 Rule Cuba 1940 1942 - Sep Sun>=1 0:00 0 S
1128 Rule Cuba 1945 1946 - Jun Sun>=1 0:00 1:00 D
1129 Rule Cuba 1945 1946 - Sep Sun>=1 0:00 0 S
1130 Rule Cuba 1965 only - Jun 1 0:00 1:00 D
1131 Rule Cuba 1965 only - Sep 30 0:00 0 S
1132 Rule Cuba 1966 only - May 29 0:00 1:00 D
1133 Rule Cuba 1966 only - Oct 2 0:00 0 S
1134 Rule Cuba 1967 only - Apr 8 0:00 1:00 D
1135 Rule Cuba 1967 1968 - Sep Sun>=8 0:00 0 S
1136 Rule Cuba 1968 only - Apr 14 0:00 1:00 D
1137 Rule Cuba 1969 1977 - Apr lastSun 0:00 1:00 D
1138 Rule Cuba 1969 1971 - Oct lastSun 0:00 0 S
1139 Rule Cuba 1972 1974 - Oct 8 0:00 0 S
1140 Rule Cuba 1975 1977 - Oct lastSun 0:00 0 S
1141 Rule Cuba 1978 only - May 7 0:00 1:00 D
1142 Rule Cuba 1978 1990 - Oct Sun>=8 0:00 0 S
1143 Rule Cuba 1979 1980 - Mar Sun>=15 0:00 1:00 D
1144 Rule Cuba 1981 1985 - May Sun>=5 0:00 1:00 D
1145 Rule Cuba 1986 1989 - Mar Sun>=14 0:00 1:00 D
1146 Rule Cuba 1990 max - Apr Sun>=1 0:00 1:00 D
1147 Rule Cuba 1991 1995 - Oct Sun>=8 0:00s 0 S
1148 Rule Cuba 1996 only - Oct Sun>=1 0:00s 0 S
1149 Rule Cuba 1997 max - Oct Sun>=8 0:00s 0 S
1151 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1152 Zone America/Havana -5:29:28 - LMT 1890
1153 -5:30 - HMT 1925 Jul 19 12:00 # Havana MT
1157 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1158 Zone America/Dominica -4:05:36 - LMT 1911 Jul 1 0:01 # Roseau
1161 # Dominican Republic
1162 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1163 Rule DR 1966 only - Oct 30 0:00 1:00 D
1164 Rule DR 1967 only - Feb 28 0:00 0 S
1165 Rule DR 1969 1973 - Oct lastSun 0:00 0:30 HD
1166 Rule DR 1970 only - Feb 21 0:00 0 S
1167 Rule DR 1971 only - Jan 20 0:00 0 S
1168 Rule DR 1972 1974 - Jan 21 0:00 0 S
1169 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1170 Zone America/Santo_Domingo -4:39:36 - LMT 1890
1171 -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT
1172 -5:00 DR E%sT 1974 Oct 27
1176 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1177 Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D
1178 Rule Salv 1987 1988 - Sep lastSun 0:00 0 S
1179 # There are too many San Salvadors elsewhere, so we'll use `El Salvador'.
1180 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1181 Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador
1185 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1186 Zone America/Grenada -4:07:00 - LMT 1911 Jul # St George's
1190 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1191 Zone America/Guadeloupe -4:06:08 - LMT 1911 Jun 8 # Pointe a Pitre
1195 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1196 Rule Guat 1973 only - Nov 25 0:00 1:00 D
1197 Rule Guat 1974 only - Feb 24 0:00 0 S
1198 Rule Guat 1983 only - May 21 0:00 1:00 D
1199 Rule Guat 1983 only - Sep 22 0:00 0 S
1200 Rule Guat 1991 only - Mar 23 0:00 1:00 D
1201 Rule Guat 1991 only - Sep 7 0:00 0 S
1202 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1203 Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5
1207 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1208 Rule Haiti 1983 only - May 8 0:00 1:00 D
1209 Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D
1210 Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S
1211 # Shanks says AT is 2:00, but IATA SSIM (1991/1996) says 1:00s. Go with IATA.
1212 Rule Haiti 1988 max - Apr Sun>=1 1:00s 1:00 D
1213 Rule Haiti 1988 max - Oct lastSun 1:00s 0 S
1214 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1215 Zone America/Port-au-Prince -4:49:20 - LMT 1890
1216 -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT
1220 # Shanks says 1921 Jan 1; go with Whitman's more precise Apr 1.
1221 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1222 Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr
1227 # From Bob Devine (1988-01-28):
1230 # From U. S. Naval Observatory (1989-01-19):
1231 # JAMAICA 5 H BEHIND UTC
1233 # From Shanks (1991):
1234 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1235 Zone America/Jamaica -5:07:12 - LMT 1890 # Kingston
1236 -5:07 - KMT 1912 Feb # Kingston Mean Time
1237 -5:00 - EST 1974 Jan 6 2:00
1242 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1243 Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France
1244 -4:04 - FFMT 1911 May # Fort-de-France MT
1245 -4:00 - AST 1980 Apr 6
1246 -4:00 1:00 ADT 1980 Sep 28
1250 # From Paul Eggert (1997-08-31):
1251 # Recent volcanic eruptions have forced evacuation of Plymouth, the capital.
1252 # Luckily, Olveston, the current de facto capital, has the same longitude.
1253 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1254 Zone America/Montserrat -4:08:52 - LMT 1911 Jul 1 0:01 # Olveston
1258 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1259 Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D
1260 Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S
1261 Rule Nic 1992 only - Jan 1 4:00 1:00 D
1262 Rule Nic 1992 only - Sep 24 0:00 0 S
1263 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1264 Zone America/Managua -5:45:08 - LMT 1890
1265 -5:45 - MMT 1934 Jun 23 # Managua Mean Time
1266 -6:00 - CST 1973 May
1267 -5:00 - EST 1975 Feb 16
1268 -6:00 Nic C%sT 1993 Jan 1 4:00
1272 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1273 Zone America/Panama -5:18:08 - LMT 1890
1274 -5:20 - PMT 1908 Apr 22 # Panama Mean Time
1278 # There are too many San Juans elsewhere, so we'll use `Puerto_Rico'.
1279 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1280 Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan
1281 -4:00 - AST 1942 May 3
1282 -4:00 1:00 AWT 1945 Sep 30 2:00
1286 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1287 Zone America/St_Kitts -4:10:52 - LMT 1912 Mar 2 # Basseterre
1291 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1292 Zone America/St_Lucia -4:04:00 - LMT 1890 # Castries
1293 -4:04 - CMT 1912 # Castries Mean Time
1296 # St Pierre and Miquelon
1297 # There are too many St Pierres elsewhere, so we'll use `Miquelon'.
1298 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1299 Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre
1300 -4:00 - AST 1980 May
1301 -3:00 Mont PM%sT # Pierre & Miquelon Time
1303 # St Vincent and the Grenadines
1304 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1305 Zone America/St_Vincent -4:04:56 - LMT 1890 # Kingstown
1306 -4:05 - KMT 1912 # Kingstown Mean Time
1310 # From Paul Eggert (1996-11-22):
1311 # Shanks says they use US DST rules, but IATA SSIM (1991/1996)
1312 # says they switch at midnight. Go with IATA SSIM.
1313 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1314 Rule TC 1979 1986 - Apr lastSun 0:00 1:00 D
1315 Rule TC 1979 max - Oct lastSun 0:00 0 S
1316 Rule TC 1987 max - Apr Sun>=1 0:00 1:00 D
1317 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1318 Zone America/Grand_Turk -4:44:32 - LMT 1890
1319 -5:07 - KMT 1912 Feb # Kingston Mean Time
1323 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1324 Zone America/Tortola -4:18:28 - LMT 1911 Jul # Road Town
1328 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1329 Zone America/St_Thomas -4:19:44 - LMT 1911 Jul # Charlotte Amalie