| blob | ff36fe433ea06e1502fdc1af7450079f3b5c20a0 |
1 # @(#)northamerica 7.62
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> (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 ###############################################################################
14 # United States
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 <eggert@twinsun.com> (1995-12-19):
28 # A good source for time zone historical data in the US is
29 # Thomas G. Shanks, The American Atlas (5th edition),
30 # San Diego: ACS Publications, Inc. (1991).
31 # Make sure you have the errata sheet; the book is somewhat useless without it.
32 # It is the source for the US and Puerto Rico entries below.
34 # From Paul Eggert (2001-03-06):
35 # Daylight Saving Time was first suggested as a joke by Benjamin Franklin
36 # in his whimsical essay ``An Economical Project for Diminishing the Cost
37 # of Light'' published in the Journal de Paris (1784-04-26).
38 # Not everyone is happy with the results:
39 #
40 # I don't really care how time is reckoned so long as there is some
41 # agreement about it, but I object to being told that I am saving
42 # daylight when my reason tells me that I am doing nothing of the kind.
43 # I even object to the implication that I am wasting something
44 # valuable if I stay in bed after the sun has risen. As an admirer
45 # of moonlight I resent the bossy insistence of those who want to
46 # reduce my time for enjoying it. At the back of the Daylight Saving
47 # scheme I detect the bony, blue-fingered hand of Puritanism, eager
48 # to push people into bed earlier, and get them up earlier, to make
49 # them healthy, wealthy and wise in spite of themselves.
50 #
51 # -- Robertson Davies, The Diary of Samuel Marchbanks (1947), XIX, Sunday
52 #
53 # For more about the first ten years of DST in the United States, see
54 # Robert Garland's <a href="http://www.clpgh.org/exhibit/dst.html">
55 # Ten years of daylight saving from the Pittsburgh standpoint
56 # (Carnegie Library of Pittsburgh, 1927)</a>.
57 #
58 # Shanks says that DST was called "War Time" in the US in 1918 and 1919.
59 # However, DST was imposed by the Standard Time Act of 1918, which
60 # was the first nationwide legal time standard, and apparently
61 # time was just called "Standard Time" or "Daylight Saving Time".
63 # From Arthur David Olson:
64 # US Daylight Saving Time ended on the last Sunday of *October* in 1974.
65 # See, for example, the front page of the Saturday, 1974-10-26
66 # and Sunday, 1974-10-27 editions of the Washington Post.
68 # From Arthur David Olson:
69 # Before the Uniform Time Act of 1966 took effect in 1967, observance of
70 # Daylight Saving Time in the US was by local option, except during wartime.
72 # From Arthur David Olson (2000-09-25):
73 # Last night I heard part of a rebroadcast of a 1945 Arch Oboler radio drama.
74 # In the introduction, Oboler spoke of "Eastern Peace Time."
75 # An AltaVista search turned up
76 # <a href="http://rowayton.org/rhs/hstaug45.html">:
77 # "When the time is announced over the radio now, it is 'Eastern Peace
78 # Time' instead of the old familiar 'Eastern War Time.' Peace is wonderful."
79 # </a> (August 1945) by way of confirmation.
81 # From Joseph Gallant <notquite@hotmail.com>, citing
82 # George H. Douglas, _The Early Days of Radio Broadcasting_ (1987):
83 # At 7 P.M. (Eastern War Time) [on 1945-08-14], the networks were set
84 # to switch to London for Attlee's address, but the American people
85 # never got to hear his speech live. According to one press account,
86 # CBS' Bob Trout was first to announce the word of Japan's surrender,
87 # but a few seconds later, NBC, ABC and Mutual also flashed the word
88 # of surrender, all of whom interrupting the bells of Big Ben in
89 # London which were to precede Mr. Attlee's speech.
91 # From Paul Eggert (2003-02-09): It was Robert St John, not Bob Trout. From
92 # Myrna Oliver's obituary of St John on page B16 of today's Los Angeles Times:
93 #
94 # ... a war-weary U.S. clung to radios, awaiting word of Japan's surrender.
95 # Any announcement from Asia would reach St. John's New York newsroom on a
96 # wire service teletype machine, which had prescribed signals for major news.
97 # Associated Press, for example, would ring five bells before spewing out
98 # typed copy of an important story, and 10 bells for news "of transcendental
99 # importance."
100 #
101 # On Aug. 14, stalling while talking steadily into the NBC networks' open
102 # microphone, St. John heard five bells and waited only to hear a sixth bell,
103 # before announcing confidently: "Ladies and gentlemen, World War II is over.
104 # The Japanese have agreed to our surrender terms."
105 #
106 # He had scored a 20-second scoop on other broadcasters.
108 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
109 Rule US 1918 1919 - Mar lastSun 2:00 1:00 D
110 Rule US 1918 1919 - Oct lastSun 2:00 0 S
111 Rule US 1942 only - Feb 9 2:00 1:00 W # War
112 Rule US 1945 only - Aug 14 23:00u 1:00 P # Peace
113 Rule US 1945 only - Sep 30 2:00 0 S
114 Rule US 1967 max - Oct lastSun 2:00 0 S
115 Rule US 1967 1973 - Apr lastSun 2:00 1:00 D
116 Rule US 1974 only - Jan 6 2:00 1:00 D
117 Rule US 1975 only - Feb 23 2:00 1:00 D
118 Rule US 1976 1986 - Apr lastSun 2:00 1:00 D
119 Rule US 1987 max - Apr Sun>=1 2:00 1:00 D
120 # <a href="http://thomas.loc.gov/cgi-bin/bdquery/z?d106:h.r.00177:">
121 # H.R.177
122 # </a> (introduced 1999-01-06) would change April to March in the above rule.
124 # From Bob Devine (1988-01-28):
125 # ...Alaska (and Hawaii) had the timezone names changed in 1967.
126 # old new
127 # Pacific Standard Time(PST) -same-
128 # Yukon Standard Time(YST) -same-
129 # Central Alaska S.T. (CAT) Alaska-Hawaii St[an]dard Time (AHST)
130 # Nome Standard Time (NT) Bering Standard Time (BST)
131 #
132 # ...Alaska's timezone lines were redrawn in 1983 to give only 2 tz.
133 # The YST zone now covers nearly all of the state, AHST just part
134 # of the Aleutian islands. No DST.
136 # From Paul Eggert (1995-12-19):
137 # The tables below use `NST', not `NT', for Nome Standard Time.
138 # I invented `CAWT' for Central Alaska War Time.
140 # From U. S. Naval Observatory (1989-01-19):
141 # USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON
142 # USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30
143 # USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON
144 # USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30
145 # USA MOUNTAIN 7 H BEHIND UTC DENVER
146 # USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30
147 # USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO
148 # USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30
149 # USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST)
150 # USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT)
151 # USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W
152 # USA - " - 9 H BEHIND UTC APR 3 - OCT 30
153 # USA HAWAII 10 H BEHIND UTC
154 # USA BERING 11 H BEHIND UTC SAMOA, MIDWAY
156 # From Arthur David Olson (1989-01-21):
157 # The above dates are for 1988.
158 # Note the "AKST" and "AKDT" abbreviations, the claim that there's
159 # no DST in Samoa, and the claim that there is DST in Alaska and the
160 # Aleutians.
162 # From Arthur David Olson (1988-02-13):
163 # Legal standard time zone names, from United States Code (1982 Edition and
164 # Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names
165 # up to 1967-04-01 (when most provisions of the Uniform Time Act of 1966
166 # took effect), as explained in sections 263 and 261:
167 # (none)
168 # United States standard eastern time
169 # United States standard mountain time
170 # United States standard central time
171 # United States standard Pacific time
172 # (none)
173 # United States standard Alaska time
174 # (none)
175 # Next, names from 1967-04-01 until 1983-11-30 (the date for
176 # public law 98-181):
177 # Atlantic standard time
178 # eastern standard time
179 # central standard time
180 # mountain standard time
181 # Pacific standard time
182 # Yukon standard time
183 # Alaska-Hawaii standard time
184 # Bering standard time
185 # And after 1983-11-30:
186 # Atlantic standard time
187 # eastern standard time
188 # central standard time
189 # mountain standard time
190 # Pacific standard time
191 # Alaska standard time
192 # Hawaii-Aleutian standard time
193 # Samoa standard time
194 # The law doesn't give abbreviations.
195 #
196 # From Paul Eggert (1995-12-19):
197 # Shanks uses 1983-10-30, not 1983-11-30, for the 1983 transitions.
198 # Go with Shanks.
199 #
200 # From Paul Eggert (2000-01-08), following a heads-up from Rives McDow:
201 # Public law 106-564 (2000-12-23) introduced the abbreviation
202 # "Chamorro Standard Time" for time in Guam and the Northern Marianas.
203 # See the file "australasia".
206 # US eastern time, represented by New York
208 # Connecticut, Delaware, District of Columbia, most of Florida,
209 # Georgia, southeast Indiana (Clark, Dearborn, Floyd, Harrison, and
210 # Ohio counties), eastern Kentucky, Maine, Maryland, Massachusetts,
211 # New Hampshire, New Jersey, New York, North Carolina, Ohio,
212 # Pennsylvania, Rhode Island, South Carolina, eastern Tennessee,
213 # Vermont, Virginia, West Virginia
215 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
216 Rule NYC 1920 only - Mar lastSun 2:00 1:00 D
217 Rule NYC 1920 only - Oct lastSun 2:00 0 S
218 Rule NYC 1921 1966 - Apr lastSun 2:00 1:00 D
219 Rule NYC 1921 1954 - Sep lastSun 2:00 0 S
220 Rule NYC 1955 1966 - Oct lastSun 2:00 0 S
221 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
222 Zone America/New_York -4:56:02 - LMT 1883 Nov 18 12:00
223 -5:00 US E%sT 1920
224 -5:00 NYC E%sT 1942
225 -5:00 US E%sT 1946
226 -5:00 NYC E%sT 1967
227 -5:00 US E%sT
229 # US central time, represented by Chicago
231 # Alabama, Arkansas, Florida panhandle, Illinois, western Indiana
232 # (Gibson, Jasper, Lake, LaPorte, Newton, Porter, Posey, Spencer,
233 # Vanderburgh, and Warrick counties), Iowa, most of Kansas, western
234 # Kentucky, Louisiana, Minnesota, Mississippi, Missouri, eastern
235 # Nebraska, eastern North Dakota, Oklahoma, eastern South Dakota,
236 # western Tennessee, most of Texas, Wisconsin
238 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
239 Rule Chicago 1920 only - Jun 13 2:00 1:00 D
240 Rule Chicago 1920 1921 - Oct lastSun 2:00 0 S
241 Rule Chicago 1921 only - Mar lastSun 2:00 1:00 D
242 Rule Chicago 1922 1966 - Apr lastSun 2:00 1:00 D
243 Rule Chicago 1922 1954 - Sep lastSun 2:00 0 S
244 Rule Chicago 1955 1966 - Oct lastSun 2:00 0 S
245 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
246 Zone America/Chicago -5:50:36 - LMT 1883 Nov 18 12:00
247 -6:00 US C%sT 1920
248 -6:00 Chicago C%sT 1936 Mar 1 2:00
249 -5:00 - EST 1936 Nov 15 2:00
250 -6:00 Chicago C%sT 1942
251 -6:00 US C%sT 1946
252 -6:00 Chicago C%sT 1967
253 -6:00 US C%sT
254 # Oliver County, ND switched from mountain to central time on 1992-10-25.
255 Zone America/North_Dakota/Center -6:45:12 - LMT 1883 Nov 18 12:00
256 -7:00 US M%sT 1992 Oct 25 02:00
257 -6:00 US C%sT
259 # US mountain time, represented by Denver
260 #
261 # Colorado, southern Idaho, far western Kansas, Montana, western
262 # Nebraska, Nevada border (Jackpot, Owyhee, and Mountain City),
263 # New Mexico, southwestern North Dakota, far eastern Oregon,
264 # western South Dakota, far western Texas (El Paso County, Hudspeth County,
265 # and Pine Springs and Nickel Creek in Culberson County), Utah, Wyoming
266 #
267 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
268 Rule Denver 1920 1921 - Mar lastSun 2:00 1:00 D
269 Rule Denver 1920 only - Oct lastSun 2:00 0 S
270 Rule Denver 1921 only - May 22 2:00 0 S
271 Rule Denver 1965 1966 - Apr lastSun 2:00 1:00 D
272 Rule Denver 1965 1966 - Oct lastSun 2:00 0 S
273 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
274 Zone America/Denver -6:59:56 - LMT 1883 Nov 18 12:00
275 -7:00 US M%sT 1920
276 -7:00 Denver M%sT 1942
277 -7:00 US M%sT 1946
278 -7:00 Denver M%sT 1967
279 -7:00 US M%sT
281 # US Pacific time, represented by Los Angeles
282 #
283 # California, northern Idaho, most of Nevada, most of Oregon, and Washington
284 #
285 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
286 Rule CA 1948 only - Mar 14 2:00 1:00 D
287 Rule CA 1949 only - Jan 1 2:00 0 S
288 Rule CA 1950 1966 - Apr lastSun 2:00 1:00 D
289 Rule CA 1950 1961 - Sep lastSun 2:00 0 S
290 Rule CA 1962 1966 - Oct lastSun 2:00 0 S
291 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
292 Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 12:00
293 -8:00 US P%sT 1946
294 -8:00 CA P%sT 1967
295 -8:00 US P%sT
297 # Alaska
298 # AK%sT is the modern abbreviation for -9:00 per USNO.
299 #
300 # From Paul Eggert (2001-05-30):
301 # Howse writes that Alaska switched from the Julian to the Gregorian calendar,
302 # and from east-of-GMT to west-of-GMT days, when the US bought it from Russia.
303 # This was on 1867-10-18, a Friday; the previous day was 1867-10-06 Julian,
304 # also a Friday. Include only the time zone part of this transition,
305 # ignoring the switch from Julian to Gregorian, since we can't represent
306 # the Julian calendar.
307 #
308 # As far as we know, none of the exact locations mentioned below were
309 # permanently inhabited in 1867 by anyone using either calendar.
310 # (Yakutat was colonized by the Russians in 1799, but the settlement
311 # was destroyed in 1805 by a Yakutat-kon war party.) However, there
312 # were nearby inhabitants in some cases and for our purposes perhaps
313 # it's best to simply use the official transition.
314 #
315 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
316 Zone America/Juneau 15:02:19 - LMT 1867 Oct 18
317 -8:57:41 - LMT 1900 Aug 20 12:00
318 -8:00 - PST 1942
319 -8:00 US P%sT 1946
320 -8:00 - PST 1969
321 -8:00 US P%sT 1983 Oct 30 2:00
322 -9:00 US AK%sT
323 Zone America/Yakutat 14:41:05 - LMT 1867 Oct 18
324 -9:18:55 - LMT 1900 Aug 20 12:00
325 -9:00 - YST 1942
326 -9:00 US Y%sT 1946
327 -9:00 - YST 1969
328 -9:00 US Y%sT 1983 Oct 30 2:00
329 -9:00 US AK%sT
330 Zone America/Anchorage 14:00:24 - LMT 1867 Oct 18
331 -9:59:36 - LMT 1900 Aug 20 12:00
332 -10:00 - CAT 1942
333 -10:00 US CAT/CAWT 1946
334 -10:00 - CAT 1967 Apr
335 -10:00 - AHST 1969
336 -10:00 US AH%sT 1983 Oct 30 2:00
337 -9:00 US AK%sT
338 Zone America/Nome 12:58:21 - LMT 1867 Oct 18
339 -11:01:38 - LMT 1900 Aug 20 12:00
340 -11:00 - NST 1942
341 -11:00 US N%sT 1946
342 -11:00 - NST 1967 Apr
343 -11:00 - BST 1969
344 -11:00 US B%sT 1983 Oct 30 2:00
345 -9:00 US AK%sT
346 Zone America/Adak 12:13:21 - LMT 1867 Oct 18
347 -11:46:38 - LMT 1900 Aug 20 12:00
348 -11:00 - NST 1942
349 -11:00 US N%sT 1946
350 -11:00 - NST 1967 Apr
351 -11:00 - BST 1969
352 -11:00 US B%sT 1983 Oct 30 2:00
353 -10:00 US HA%sT
354 # Shanks writes that part of southwest Alaska (e.g. Aniak)
355 # switched from -11:00 to -10:00 on 1968-09-22 at 02:00,
356 # and another part (e.g. Akiak) made the same switch five weeks later.
357 # These switches don't quite make our 1970 cutoff.
359 # Hawaii
360 #
361 # From Arthur David Olson:
362 # And then there's Hawaii.
363 # DST was observed for one day in 1933;
364 # standard time was changed by half an hour in 1947;
365 # it's always standard as of 1986.
366 #
367 # From Paul Eggert:
368 # Shanks says the 1933 experiment lasted for three weeks. Go with Shanks.
369 #
370 Zone Pacific/Honolulu -10:31:26 - LMT 1900 Jan 1 12:00
371 -10:30 - HST 1933 Apr 30 2:00
372 -10:30 1:00 HDT 1933 May 21 2:00
373 -10:30 US H%sT 1947 Jun 8 2:00
374 -10:00 - HST
376 # Now we turn to US areas that have diverged from the consensus since 1970.
378 # Arizona mostly uses MST.
380 # From Paul Eggert (2002-10-20):
381 #
382 # The information in the rest of this paragraph is derived from the
383 # <a href="http://www.dlapr.lib.az.us/links/daylight.htm">
384 # Daylight Saving Time web page (2002-01-23)</a> maintained by the
385 # Arizona State Library, Archives and Public Records.
386 # Between 1944-01-01 and 1944-04-01 the State of Arizona used standard
387 # time, but by federal law railroads, airlines, bus lines, military
388 # personnel, and some engaged in interstate commerce continued to
389 # observe war (i.e., daylight saving) time. The 1944-03-17 Phoenix
390 # Gazette says that was the date the law changed, and that 04-01 was
391 # the date the state's clocks would change. In 1945 the State of
392 # Arizona used standard time all year, again with exceptions only as
393 # mandated by federal law. Arizona observed DST in 1967, but Arizona
394 # Laws 1968, ch. 183 (effective 1968-03-21) repealed DST.
395 #
396 # Shanks says the 1944 experiment came to an end on 1944-03-17.
397 # Go with the Arizona State Library instead.
399 Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 12:00
400 -7:00 US M%sT 1944 Jan 1 00:01
401 -7:00 - MST 1944 Apr 1 00:01
402 -7:00 US M%sT 1944 Oct 1 00:01
403 -7:00 - MST 1967
404 -7:00 US M%sT 1968 Mar 21
405 -7:00 - MST
406 # From Arthur David Olson (1988-02-13):
407 # A writer from the Inter Tribal Council of Arizona, Inc.,
408 # notes in private correspondence dated 12/28/87 that "Presently, only the
409 # Navajo Nation participates in the Daylight Saving Time policy, due to its
410 # large size and location in three states." (The "only" means that other
411 # tribal nations don't use DST.)
413 Link America/Denver America/Shiprock
415 # Southern Idaho and eastern Oregon switched four weeks late in 1974.
416 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
417 Zone America/Boise -7:44:49 - LMT 1883 Nov 18 12:00
418 -8:00 US P%sT 1923 May 13 2:00
419 -7:00 US M%sT 1974
420 -7:00 - MST 1974 Feb 3 2:00
421 -7:00 US M%sT
423 # Indiana
424 #
425 # For a map of Indiana's time zone regions, see:
426 # <a href="http://www.mccsc.edu/time.html">
427 # What time is it in Indiana?
428 # </a> (1999-04-06)
429 #
430 # From Paul Eggert (1995-12-19):
431 # Indiana generally observes either EST all year, or CST/CDT,
432 # but areas near Cincinnati and Louisville use those cities' timekeeping
433 # and in 1969 and 1970 the whole state observed daylight time;
434 # and there are other exceptions as noted below.
435 # Shanks partitions Indiana into 345 regions, each with its own time history,
436 # and writes ``Even newspaper reports present contradictory information.''
437 # Fortunately, most of the complexity occurred before our cutoff date of 1970.
438 #
439 # Since 1970, EST-only Indiana has been like America/Indianapolis,
440 # with exceptions noted below for Crawford, Starke, and Switzerland counties.
441 # The parts of Indiana not listed below have been like America/Chicago,
442 # America/Louisville, or America/New_York.
443 #
444 # Other than Indianapolis, the Indiana place names are so nondescript
445 # that they would be ambiguous if we left them at the `America' level.
446 # So we reluctantly put them all in a subdirectory `America/Indiana'.
447 #
448 # Most of EST-only Indiana last observed DST in 1970.
450 # From Paul Eggert (2001-03-06), following a tip by Markus Kuhn:
451 # Pam Belluck reported in the New York Times (2001-01-31) that the
452 # Indiana Legislature is considering a bill to adopt DST statewide.
453 # Her article mentioned Vevay, whose post office observes a different
454 # time zone from Danner's Hardware across the street.
456 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
457 Rule Indianapolis 1941 only - Jun 22 2:00 1:00 D
458 Rule Indianapolis 1941 1954 - Sep lastSun 2:00 0 S
459 Rule Indianapolis 1946 1954 - Apr lastSun 2:00 1:00 D
460 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
461 Zone America/Indianapolis -5:44:38 - LMT 1883 Nov 18 12:00
462 -6:00 US C%sT 1920
463 -6:00 Indianapolis C%sT 1942
464 -6:00 US C%sT 1946
465 -6:00 Indianapolis C%sT 1955 Apr 24 2:00
466 -5:00 - EST 1957 Sep 29 2:00
467 -6:00 - CST 1958 Apr 27 2:00
468 -5:00 - EST 1969
469 -5:00 US E%sT 1971
470 -5:00 - EST
471 Link America/Indianapolis America/Indiana/Indianapolis
472 #
473 # Part of Crawford County, Indiana, last observed DST in 1975,
474 # and left its clocks alone in 1974.
475 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
476 Rule Marengo 1951 only - Apr lastSun 2:00 1:00 D
477 Rule Marengo 1951 only - Sep lastSun 2:00 0 S
478 Rule Marengo 1954 1960 - Apr lastSun 2:00 1:00 D
479 Rule Marengo 1954 1960 - Sep lastSun 2:00 0 S
480 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
481 Zone America/Indiana/Marengo -5:45:23 - LMT 1883 Nov 18 12:00
482 -6:00 US C%sT 1951
483 -6:00 Marengo C%sT 1961 Apr 30 2:00
484 -5:00 - EST 1969
485 -5:00 US E%sT 1974 Jan 6 2:00
486 -6:00 1:00 CDT 1974 Oct 27 2:00
487 -5:00 US E%sT 1976
488 -5:00 - EST
489 #
490 # Starke County, Indiana
491 # From Arthur David Olson (1991-10-28):
492 # An article on page A3 of the Sunday, 1991-10-27 Washington Post
493 # notes that Starke County switched from Central time to Eastern time as of
494 # 1991-10-27.
495 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
496 Rule Starke 1947 1961 - Apr lastSun 2:00 1:00 D
497 Rule Starke 1947 1954 - Sep lastSun 2:00 0 S
498 Rule Starke 1955 1956 - Oct lastSun 2:00 0 S
499 Rule Starke 1957 1958 - Sep lastSun 2:00 0 S
500 Rule Starke 1959 1961 - Oct lastSun 2:00 0 S
501 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
502 Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 12:00
503 -6:00 US C%sT 1947
504 -6:00 Starke C%sT 1962 Apr 29 2:00
505 -5:00 - EST 1963 Oct 27 2:00
506 -6:00 US C%sT 1991 Oct 27 2:00
507 -5:00 - EST
508 #
509 # Switzerland County, Indiana, last observed DST in 1972.
510 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
511 Zone America/Indiana/Vevay -5:40:16 - LMT 1883 Nov 18 12:00
512 -6:00 US C%sT 1954 Apr 25 2:00
513 -5:00 - EST 1969
514 -5:00 US E%sT 1973
515 -5:00 - EST
517 # Part of Kentucky left its clocks alone in 1974.
518 # This also includes a part of Indiana immediately adjacent to Louisville.
519 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
520 Rule Louisville 1921 only - May 1 2:00 1:00 D
521 Rule Louisville 1921 only - Sep 1 2:00 0 S
522 Rule Louisville 1941 1961 - Apr lastSun 2:00 1:00 D
523 Rule Louisville 1941 only - Sep lastSun 2:00 0 S
524 Rule Louisville 1946 only - Jun 2 2:00 0 S
525 Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S
526 Rule Louisville 1956 1960 - Oct lastSun 2:00 0 S
527 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
528 Zone America/Louisville -5:43:02 - LMT 1883 Nov 18 12:00
529 -6:00 US C%sT 1921
530 -6:00 Louisville C%sT 1942
531 -6:00 US C%sT 1946
532 -6:00 Louisville C%sT 1961 Jul 23 2:00
533 -5:00 - EST 1968
534 -5:00 US E%sT 1974 Jan 6 2:00
535 -6:00 1:00 CDT 1974 Oct 27 2:00
536 -5:00 US E%sT
537 Link America/Louisville America/Kentucky/Louisville
538 #
539 # Wayne, Clinton, and Russell Counties, Kentucky
540 #
541 # From
542 # <a href="http://www.lake-cumberland.com/life/archive/news990129time.shtml">
543 # Lake Cumberland LIFE
544 # </a> (1999-01-29) via WKYM-101.7:
545 # Clinton County has joined Wayne County in asking the DoT to change from
546 # the Central to the Eastern time zone.... The Wayne County government made
547 # the same request in December. And while Russell County officials have not
548 # taken action, the majority of respondents to a poll conducted there in
549 # August indicated they would like to change to "fast time" also.
550 # The three Lake Cumberland counties are the farthest east of any U.S.
551 # location in the Central time zone.
552 #
553 # From Rich Wales (2000-08-29):
554 # After prolonged debate, and despite continuing deep differences of opinion,
555 # Wayne County (central Kentucky) is switching from Central (-0600) to Eastern
556 # (-0500) time. They won't "fall back" this year. See Sara Shipley,
557 # The difference an hour makes, Nando Times (2000-08-29 15:33 -0400).
558 #
559 # From Paul Eggert (2001-07-16):
560 # The final rule was published in the
561 # <a href="http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=2000_register&docid=fr17au00-22">
562 # Federal Register 65, 160 (2000-08-17), page 50154-50158.
563 # </a>
564 #
565 Zone America/Kentucky/Monticello -5:39:24 - LMT 1883 Nov 18 12:00
566 -6:00 US C%sT 1946
567 -6:00 - CST 1968
568 -6:00 US C%sT 2000 Oct 29 2:00
569 -5:00 US E%sT
572 # From Rives McDow (2000-08-30):
573 # Here ... are all the changes in the US since 1985.
574 # Kearny County, KS (put all of county on central;
575 # previously split between MST and CST) ... 1990-10
576 # Starke County, IN (from CST to EST) ... 1991-10
577 # Oliver County, ND (from MST to CST) ... 1992-10
578 # West Wendover, NV (from PST TO MST) ... 1999-10
579 # Wayne County, KY (from CST to EST) ... 2000-10
580 #
581 # From Paul Eggert (2001-07-17):
582 # We don't know where the line used to be within Kearny County, KS,
583 # so omit that change for now.
584 # See America/Indiana/Knox for the Starke County, IN change.
585 # See America/North_Dakota/Center for the Oliver County, ND change.
586 # West Wendover, NV officially switched from Pacific to mountain time on
587 # 1999-10-31. See the
588 # <a href="http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=1999_register&docid=fr21oc99-15">
589 # Federal Register 64, 203 (1999-10-21), page 56705-56707.
590 # </a>
591 # However, the Federal Register says that West Wendover already operated
592 # on mountain time, and the rule merely made this official;
593 # hence a separate tz entry is not needed.
595 # Michigan
596 #
597 # From Bob Devine (1988-01-28):
598 # Michigan didn't observe DST from 1968 to 1973.
599 #
600 # From Paul Eggert (1999-03-31):
601 # Shanks writes that Michigan started using standard time on 1885-09-18,
602 # but Howse writes (pp 124-125, referring to Popular Astronomy, 1901-01)
603 # that Detroit kept
604 #
605 # local time until 1900 when the City Council decreed that clocks should
606 # be put back twenty-eight minutes to Central Standard Time. Half the
607 # city obeyed, half refused. After considerable debate, the decision
608 # was rescinded and the city reverted to Sun time. A derisive offer to
609 # erect a sundial in front of the city hall was referred to the
610 # Committee on Sewers. Then, in 1905, Central time was adopted
611 # by city vote.
612 #
613 # This story is too entertaining to be false, so go with Howse over Shanks.
614 #
615 # From Paul Eggert (2001-03-06):
616 # Garland (1927) writes ``Cleveland and Detroit advanced their clocks
617 # one hour in 1914.'' This change is not in Shanks. We have no more
618 # info, so omit this for now.
619 #
620 # Most of Michigan observed DST from 1973 on, but was a bit late in 1975.
621 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
622 Rule Detroit 1948 only - Apr lastSun 2:00 1:00 D
623 Rule Detroit 1948 only - Sep lastSun 2:00 0 S
624 Rule Detroit 1967 only - Jun 14 2:00 1:00 D
625 Rule Detroit 1967 only - Oct lastSun 2:00 0 S
626 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
627 Zone America/Detroit -5:32:11 - LMT 1905
628 -6:00 - CST 1915 May 15 2:00
629 -5:00 - EST 1942
630 -5:00 US E%sT 1946
631 -5:00 Detroit E%sT 1973
632 -5:00 US E%sT 1975
633 -5:00 - EST 1975 Apr 27 2:00
634 -5:00 US E%sT
635 #
636 # The Michigan border with Wisconsin switched from EST to CST/CDT in 1973.
637 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
638 Rule Menominee 1946 only - Apr lastSun 2:00 1:00 D
639 Rule Menominee 1946 only - Sep lastSun 2:00 0 S
640 Rule Menominee 1966 only - Apr lastSun 2:00 1:00 D
641 Rule Menominee 1966 only - Oct lastSun 2:00 0 S
642 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
643 Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00
644 -6:00 US C%sT 1946
645 -6:00 Menominee C%sT 1969 Apr 27 2:00
646 -5:00 - EST 1973 Apr 29 2:00
647 -6:00 US C%sT
649 # Navassa
650 # administered by the US Fish and Wildlife Service
651 # claimed by US under the provisions of the 1856 Guano Islands Act
652 # also claimed by Haiti
653 # occupied 1857/1900 by the Navassa Phosphate Co
654 # US lighthouse 1917/1996-09
655 # currently uninhabited
656 # see Mark Fineman, ``An Isle Rich in Guano and Discord'',
657 # _Los Angeles Times_ (1998-11-10), A1, A10; it cites
658 # Jimmy Skaggs, _The Great Guano Rush_ (1994).
660 # Old names, for S5 users
662 # Link LINK-FROM LINK-TO
663 Link America/New_York EST5EDT
664 Link America/Chicago CST6CDT
665 Link America/Denver MST7MDT
666 Link America/Los_Angeles PST8PDT
667 Link America/Indianapolis EST
668 Link America/Phoenix MST
669 Link Pacific/Honolulu HST
671 ################################################################################
674 # From Paul Eggert <eggert@twinsun.com> (1999-10-29):
675 # A good source for time zone historical data outside the US is
676 # Thomas G. Shanks, The International Atlas (5th edition),
677 # San Diego: ACS Publications, Inc. (1999).
678 #
679 # Gwillim Law writes that a good source
680 # for recent time zone data is the International Air Transport
681 # Association's Standard Schedules Information Manual (IATA SSIM),
682 # published semiannually. Law sent in several helpful summaries
683 # of the IATA's data after 1990.
684 #
685 # Except where otherwise noted, Shanks is the source for entries through 1990,
686 # and IATA SSIM is the source for entries after 1990.
687 #
688 # Another source occasionally used is Edward W. Whitman, World Time Differences,
689 # Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated), which
690 # I found in the UCLA library.
691 #
692 # See the `europe' file for Greenland.
694 # Canada
696 # From Alain LaBont<e'> <ALB@immedia.ca> (1994-11-14):
697 # I post here the time zone abbreviations standardized in Canada
698 # for both English and French in the CAN/CSA-Z234.4-89 standard....
699 #
700 # UTC Standard time Daylight savings time
701 # offset French English French English
702 # -2:30 - - HAT NDT
703 # -3 - - HAA ADT
704 # -3:30 HNT NST - -
705 # -4 HNA AST HAE EDT
706 # -5 HNE EST HAC CDT
707 # -6 HNC CST HAR MDT
708 # -7 HNR MST HAP PDT
709 # -8 HNP PST HAY YDT
710 # -9 HNY YST - -
711 #
712 # HN: Heure Normale ST: Standard Time
713 # HA: Heure Avanc<e'>e DT: Daylight saving Time
714 #
715 # A: de l'Atlantique Atlantic
716 # C: du Centre Central
717 # E: de l'Est Eastern
718 # M: Mountain
719 # N: Newfoundland
720 # P: du Pacifique Pacific
721 # R: des Rocheuses
722 # T: de Terre-Neuve
723 # Y: du Yukon Yukon
724 #
725 # From Paul Eggert <eggert@twinsun.com> (1994-11-22):
726 # Alas, this sort of thing must be handled by localization software.
728 # Unless otherwise specified, the data for Canada are all from Shanks.
730 # From Paul Eggert (2000-10-02):
731 # H. David Matthews and Mary Vincent's map
732 # <a href="http://www.canadiangeographic.ca/SO98/geomap.htm">
733 # "It's about TIME", _Canadian Geographic_ (September-October 1998)
734 # </a> contains detailed boundaries for regions observing nonstandard
735 # time and daylight saving time arrangements in Canada circa 1998.
736 #
737 # INMS, the Institute for National Measurement Standards in Ottawa, has
738 # <a href="http://www.nrc.ca/inms/time/tze.html">
739 # information about standard and daylight saving time zones in Canada.
740 # </a> (updated periodically).
741 # Its unofficial information is often taken from Matthews and Vincent.
743 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
744 Rule Canada 1918 only - Apr 14 2:00 1:00 D
745 Rule Canada 1918 only - Oct 31 2:00 0 S
746 Rule Canada 1942 only - Feb 9 2:00 1:00 W
747 Rule Canada 1945 only - Sep 30 2:00 0 S
748 Rule Canada 1974 1986 - Apr lastSun 2:00 1:00 D
749 Rule Canada 1974 max - Oct lastSun 2:00 0 S
750 Rule Canada 1987 max - Apr Sun>=1 2:00 1:00 D
753 # Newfoundland (and far southeast Labrador)
755 # From Paul Eggert (2000-10-02):
756 # Matthews and Vincent (1998) write that Labrador should use NST/NDT,
757 # but the only part of Labrador that follows the rules is the
758 # southeast corner, including Port Hope Simpson and Mary's Harbour,
759 # but excluding, say, Black Tickle.
761 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
762 Rule StJohns 1917 1918 - Apr Sun>=8 2:00 1:00 D
763 Rule StJohns 1917 only - Sep 17 2:00 0 S
764 Rule StJohns 1918 only - Oct 31 2:00 0 S
765 # Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks.
766 Rule StJohns 1919 only - May 5 23:00 1:00 D
767 Rule StJohns 1919 only - Aug 12 23:00 0 S
768 # For 1931-1935 Whitman gives Apr same date; go with Shanks.
769 Rule StJohns 1920 1935 - May Sun>=1 23:00 1:00 D
770 Rule StJohns 1920 1935 - Oct lastSun 23:00 0 S
771 # For 1936-1941 Shanks gives May Mon>=9 and Oct Mon>=2; go with Whitman.
772 Rule StJohns 1936 1941 - May Sun>=8 0:00 1:00 D
773 Rule StJohns 1936 1941 - Oct Sun>=1 0:00 0 S
774 # Shanks gives 1942 May 11 - 1945 Sep 30; go with Whitman.
775 Rule StJohns 1942 only - Mar 1 0:00 1:00 W
776 Rule StJohns 1942 only - Dec 31 0:00 0 S
777 Rule StJohns 1943 only - May 30 0:00 1:00 W
778 Rule StJohns 1943 only - Sep 5 0:00 0 S
779 Rule StJohns 1944 only - Jul 10 0:00 1:00 W
780 Rule StJohns 1944 only - Sep 2 0:00 0 S
781 Rule StJohns 1945 only - Jan 1 0:00 1:00 W
782 Rule StJohns 1945 only - Oct 7 2:00 0 S
783 # For 1946-9 Whitman gives May 5,4,9,1 - Oct 1,5,3,2, and for 1950 he gives
784 # Apr 30 - Sep 24; go with Shanks.
785 Rule StJohns 1946 1950 - May Sun>=8 2:00 1:00 D
786 Rule StJohns 1946 1950 - Oct Sun>=2 2:00 0 S
787 Rule StJohns 1951 1986 - Apr lastSun 2:00 1:00 D
788 Rule StJohns 1951 1959 - Sep lastSun 2:00 0 S
789 Rule StJohns 1960 1986 - Oct lastSun 2:00 0 S
790 # From Paul Eggert (2000-10-02):
791 # INMS (2000-09-12) says that, since 1988 at least, Newfoundland switches
792 # at 00:01 local time. For now, assume it started in 1987.
793 Rule StJohns 1987 only - Apr Sun>=1 0:01 1:00 D
794 Rule StJohns 1987 max - Oct lastSun 0:01 0 S
795 Rule StJohns 1988 only - Apr Sun>=1 0:01 2:00 DD
796 Rule StJohns 1989 max - Apr Sun>=1 0:01 1:00 D
797 # St John's has an apostrophe, but Posix file names can't have apostrophes.
798 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
799 Zone America/St_Johns -3:30:52 - LMT 1884
800 -3:30:52 StJohns N%sT 1935 Mar 30
801 -3:30 StJohns N%sT
804 # most of east Labrador
806 # The name `Happy Valley-Goose Bay' is too long; use `Goose Bay'.
807 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
808 Zone America/Goose_Bay -4:01:40 - LMT 1884 # Happy Valley-Goose Bay
809 -3:30:52 StJohns NST 1919
810 -3:30:52 - NST 1935 Mar 30
811 -3:30 - NST 1936
812 -3:30 StJohns N%sT 1966 Mar 15 2:00
813 -4:00 StJohns A%sT
816 # west Labrador, New Brunswick, Nova Scotia, Prince Edward I
818 # From Paul Eggert (1996-06-12):
819 # Shanks writes that since 1970 most of this region has been like Halifax.
820 # Many locales did not observe peacetime DST until 1972;
821 # Glace Bay, NS is the largest that we know of.
822 # Shanks also writes that Liverpool, NS was the only town in Canada to observe
823 # DST in 1971 but not 1970; for now we'll assume this is a typo.
825 # From Paul Eggert (2000-10-02):
826 # INMS (2000-09-12) says that, since 1988 at least, New Brunswick switches
827 # at 00:01 local time. FIXME: verify and create a new Zone for this.
830 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
831 Rule Halifax 1916 only - Apr 1 0:00 1:00 D
832 Rule Halifax 1916 only - Oct 1 0:00 0 S
833 Rule Halifax 1918 only - Apr 14 2:00 1:00 D
834 Rule Halifax 1918 only - Oct 31 2:00 0 S
835 Rule Halifax 1920 only - May 9 0:00 1:00 D
836 Rule Halifax 1920 only - Aug 29 0:00 0 S
837 Rule Halifax 1921 only - May 6 0:00 1:00 D
838 Rule Halifax 1921 1922 - Sep 5 0:00 0 S
839 Rule Halifax 1922 only - Apr 30 0:00 1:00 D
840 Rule Halifax 1923 1925 - May Sun>=1 0:00 1:00 D
841 Rule Halifax 1923 only - Sep 4 0:00 0 S
842 Rule Halifax 1924 only - Sep 15 0:00 0 S
843 Rule Halifax 1925 only - Sep 28 0:00 0 S
844 Rule Halifax 1926 only - May 16 0:00 1:00 D
845 Rule Halifax 1926 only - Sep 13 0:00 0 S
846 Rule Halifax 1927 only - May 1 0:00 1:00 D
847 Rule Halifax 1927 only - Sep 26 0:00 0 S
848 Rule Halifax 1928 1931 - May Sun>=8 0:00 1:00 D
849 Rule Halifax 1928 only - Sep 9 0:00 0 S
850 Rule Halifax 1929 only - Sep 3 0:00 0 S
851 Rule Halifax 1930 only - Sep 15 0:00 0 S
852 Rule Halifax 1931 1932 - Sep Mon>=24 0:00 0 S
853 Rule Halifax 1933 only - Apr 30 0:00 1:00 D
854 Rule Halifax 1933 only - Oct 2 0:00 0 S
855 Rule Halifax 1934 only - May 20 0:00 1:00 D
856 Rule Halifax 1934 only - Sep 16 0:00 0 S
857 Rule Halifax 1935 only - Jun 2 0:00 1:00 D
858 Rule Halifax 1935 only - Sep 30 0:00 0 S
859 Rule Halifax 1936 only - Jun 1 0:00 1:00 D
860 Rule Halifax 1936 only - Sep 14 0:00 0 S
861 Rule Halifax 1937 1938 - May Sun>=1 0:00 1:00 D
862 Rule Halifax 1937 1941 - Sep Mon>=24 0:00 0 S
863 Rule Halifax 1939 only - May 28 0:00 1:00 D
864 Rule Halifax 1940 1941 - May Sun>=1 0:00 1:00 D
865 Rule Halifax 1942 only - Feb 9 2:00 1:00 W
866 Rule Halifax 1945 1959 - Sep lastSun 2:00 0 S
867 Rule Halifax 1946 1959 - Apr lastSun 2:00 1:00 D
868 Rule Halifax 1962 1986 - Apr lastSun 2:00 1:00 D
869 Rule Halifax 1962 max - Oct lastSun 2:00 0 S
870 Rule Halifax 1987 max - Apr Sun>=1 2:00 1:00 D
871 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
872 Zone America/Halifax -4:14:24 - LMT 1902 Jun 15
873 -4:00 Halifax A%sT
874 Zone America/Glace_Bay -3:59:48 - LMT 1902 Jun 15
875 -4:00 Canada A%sT 1953
876 -4:00 Halifax A%sT 1954
877 -4:00 - AST 1972
878 -4:00 Halifax A%sT
881 # Ontario, Quebec
883 # From Paul Eggert (1996-06-12):
884 # Shanks writes that since 1970 most of this region has been like Montreal.
885 # Thunder Bay skipped DST in 1973.
886 # Many smaller locales did not observe peacetime DST until 1974;
887 # Nipigon (EST) and Rainy River (CST) are the largest that we know of.
888 # Far west Ontario is like Winnipeg; far east Quebec is like Halifax.
890 # From Paul Eggert (1997-10-17):
891 # msb@sq.com writes that an article in the 1997-10-14 Toronto Star
892 # says that Atikokan, Ontario currently does not observe DST,
893 # but will vote on 11-10 whether to use EST/EDT.
894 # He also writes that the
895 # <a href="http://www.gov.on.ca/MBS/english/publications/statregs/conttext.html">
896 # Ontario Time Act (1990, Chapter T.9)
897 # </a>
898 # says that Ontario east of 90W uses EST/EDT, and west of 90W uses CST/CDT.
899 # Officially Atikokan is therefore on CST/CDT, and most likely this report
900 # concerns a non-official time observed as a matter of local practice.
901 # For what it's worth, Shanks says that Atikokan has agreed with
902 # Rainy River ever since standard time was introduced.
904 # From Paul Eggert (2000-10-02):
905 # Matthews and Vincent (1998) write that Atikokan, Pickle Lake, and
906 # New Osnaburgh observe CST all year, that Big Trout Lake observes
907 # CST/CDT, and that Upsala and Shebandowan observe EST/EDT, all in
908 # violation of the official Ontario rules.
909 # They also write that Quebec east of the -63 meridian is supposed to
910 # observe AST, but residents as far east as Natashquan use EST/EDT,
911 # and residents east of Natashquan use AST.
912 # We probably need Zones for far east Quebec and for Atikokan,
913 # but we don't know when their practices started.
915 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
916 Rule Mont 1917 only - Mar 25 2:00 1:00 D
917 Rule Mont 1917 only - Apr 24 0:00 0 S
918 Rule Mont 1918 only - Apr 14 2:00 1:00 D
919 Rule Mont 1918 only - Oct 31 2:00 0 S
920 Rule Mont 1919 only - Mar 31 2:30 1:00 D
921 Rule Mont 1919 only - Oct 25 2:30 0 S
922 Rule Mont 1920 only - May 2 2:30 1:00 D
923 Rule Mont 1920 only - Oct 3 2:30 0 S
924 Rule Mont 1921 only - May 1 2:00 1:00 D
925 Rule Mont 1921 only - Oct 2 2:30 0 S
926 Rule Mont 1922 only - Apr 30 2:00 1:00 D
927 Rule Mont 1922 only - Oct 1 2:30 0 S
928 Rule Mont 1924 only - May 17 2:00 1:00 D
929 Rule Mont 1924 1926 - Sep lastSun 2:30 0 S
930 Rule Mont 1925 1926 - May Sun>=1 2:00 1:00 D
931 Rule Mont 1927 only - May 1 0:00 1:00 D
932 Rule Mont 1927 1932 - Sep Sun>=25 0:00 0 S
933 Rule Mont 1928 1931 - Apr Sun>=25 0:00 1:00 D
934 Rule Mont 1932 only - May 1 0:00 1:00 D
935 Rule Mont 1933 1940 - Apr Sun>=24 0:00 1:00 D
936 Rule Mont 1933 only - Oct 1 0:00 0 S
937 Rule Mont 1934 1939 - Sep Sun>=24 0:00 0 S
938 Rule Mont 1945 1948 - Sep lastSun 2:00 0 S
939 Rule Mont 1946 1986 - Apr lastSun 2:00 1:00 D
940 Rule Mont 1949 1950 - Oct lastSun 2:00 0 S
941 Rule Mont 1951 1956 - Sep lastSun 2:00 0 S
942 Rule Mont 1957 max - Oct lastSun 2:00 0 S
943 Rule Mont 1987 max - Apr Sun>=1 2:00 1:00 D
944 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
945 Zone America/Montreal -4:54:16 - LMT 1884
946 -5:00 Mont E%sT
947 Zone America/Thunder_Bay -5:57:00 - LMT 1895
948 -5:00 Canada E%sT 1970
949 -5:00 Mont E%sT 1973
950 -5:00 - EST 1974
951 -5:00 Canada E%sT
952 Zone America/Nipigon -5:53:04 - LMT 1895
953 -5:00 Canada E%sT
954 Zone America/Rainy_River -6:17:56 - LMT 1895
955 -6:00 Canada C%sT
958 # Manitoba
960 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
961 Rule Winn 1916 only - Apr 23 0:00 1:00 D
962 Rule Winn 1916 only - Sep 17 0:00 0 S
963 Rule Winn 1918 only - Apr 14 2:00 1:00 D
964 Rule Winn 1918 only - Oct 31 2:00 0 S
965 Rule Winn 1937 only - May 16 2:00 1:00 D
966 Rule Winn 1937 only - Sep 26 2:00 0 S
967 Rule Winn 1942 only - Feb 9 2:00 1:00 W
968 Rule Winn 1945 only - Sep lastSun 2:00 0 S
969 Rule Winn 1946 only - May 12 2:00 1:00 D
970 Rule Winn 1946 only - Oct 13 2:00 0 S
971 Rule Winn 1947 1949 - Apr lastSun 2:00 1:00 D
972 Rule Winn 1947 1949 - Sep lastSun 2:00 0 S
973 Rule Winn 1950 only - May 1 2:00 1:00 D
974 Rule Winn 1950 only - Sep 30 2:00 0 S
975 Rule Winn 1951 1960 - Apr lastSun 2:00 1:00 D
976 Rule Winn 1951 1958 - Sep lastSun 2:00 0 S
977 Rule Winn 1959 only - Oct lastSun 2:00 0 S
978 Rule Winn 1960 only - Sep lastSun 2:00 0 S
979 Rule Winn 1963 only - Apr lastSun 2:00 1:00 D
980 Rule Winn 1963 only - Sep 22 2:00 0 S
981 Rule Winn 1966 1986 - Apr lastSun 2:00 1:00 D
982 Rule Winn 1966 1986 - Oct lastSun 2:00 0 S
983 Rule Winn 1987 max - Apr Sun>=1 2:00 1:00 D
984 # From Paul Eggert (2000-10-02):
985 # INMS (2000-09-12) says that, since 1988 at least, Manitoba switches from
986 # DST at 03:00 local time. For now, assume it started in 1987.
987 Rule Winn 1987 max - Oct lastSun 2:00s 0 S
988 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
989 Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16
990 -6:00 Winn C%sT
993 # Saskatchewan
995 # From Paul Eggert (2000-10-02):
996 # Shanks writes that since 1970 most of this region has been like Regina.
997 # Some western towns (e.g. Swift Current) switched from MST/MDT to CST in 1972.
998 # Other western towns (e.g. Lloydminster) are like Edmonton.
999 # Matthews and Vincent (1998) write that Denare Beach and Creighton
1000 # are like Winnipeg, in violation of Saskatchewan law.
1002 # From W. Jones <jones@skdad.usask.ca> (1992-11-06):
1003 # The. . .below is based on information I got from our law library, the
1004 # provincial archives, and the provincial Community Services department.
1005 # A precise history would require digging through newspaper archives, and
1006 # since you didn't say what you wanted, I didn't bother.
1007 #
1008 # Saskatchewan is split by a time zone meridian (105W) and over the years
1009 # the boundary became pretty ragged as communities near it reevaluated
1010 # their affiliations in one direction or the other. In 1965 a provincial
1011 # referendum favoured legislating common time practices.
1012 #
1013 # On 15 April 1966 the Time Act (c. T-14, Revised Statutes of
1014 # Saskatchewan 1978) was proclaimed, and established that the eastern
1015 # part of Saskatchewan would use CST year round, that districts in
1016 # northwest Saskatchewan would by default follow CST but could opt to
1017 # follow Mountain Time rules (thus 1 hour difference in the winter and
1018 # zero in the summer), and that districts in southwest Saskatchewan would
1019 # by default follow MT but could opt to follow CST.
1020 #
1021 # It took a few years for the dust to settle (I know one story of a town
1022 # on one time zone having its school in another, such that a mom had to
1023 # serve her family lunch in two shifts), but presently it seems that only
1024 # a few towns on the border with Alberta (e.g. Lloydminster) follow MT
1025 # rules any more; all other districts appear to have used CST year round
1026 # since sometime in the 1960s.
1028 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1029 Rule Regina 1918 only - Apr 14 2:00 1:00 D
1030 Rule Regina 1918 only - Oct 31 2:00 0 S
1031 Rule Regina 1930 1934 - May Sun>=1 0:00 1:00 D
1032 Rule Regina 1930 1934 - Oct Sun>=1 0:00 0 S
1033 Rule Regina 1937 1941 - Apr Sun>=8 0:00 1:00 D
1034 Rule Regina 1937 only - Oct Sun>=8 0:00 0 S
1035 Rule Regina 1938 only - Oct Sun>=1 0:00 0 S
1036 Rule Regina 1939 1941 - Oct Sun>=8 0:00 0 S
1037 Rule Regina 1942 only - Feb 9 2:00 1:00 W
1038 Rule Regina 1945 only - Sep lastSun 2:00 0 S
1039 Rule Regina 1946 only - Apr Sun>=8 2:00 1:00 D
1040 Rule Regina 1946 only - Oct Sun>=8 2:00 0 S
1041 Rule Regina 1947 1959 - Apr lastSun 2:00 1:00 D
1042 Rule Regina 1947 1958 - Sep lastSun 2:00 0 S
1043 Rule Regina 1959 only - Oct lastSun 2:00 0 S
1044 #
1045 Rule Swift 1957 only - Apr lastSun 2:00 1:00 D
1046 Rule Swift 1957 only - Oct lastSun 2:00 0 S
1047 Rule Swift 1959 1961 - Apr lastSun 2:00 1:00 D
1048 Rule Swift 1959 only - Oct lastSun 2:00 0 S
1049 Rule Swift 1960 1961 - Sep lastSun 2:00 0 S
1050 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1051 Zone America/Regina -6:58:36 - LMT 1905 Sep
1052 -7:00 Regina M%sT 1960 Apr lastSun 2:00
1053 -6:00 - CST
1054 Zone America/Swift_Current -7:11:20 - LMT 1905 Sep
1055 -7:00 Canada M%sT 1946 Apr lastSun 2:00
1056 -7:00 Regina M%sT 1950
1057 -7:00 Swift M%sT 1972 Apr lastSun 2:00
1058 -6:00 - CST
1061 # Alberta
1063 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1064 Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D
1065 Rule Edm 1918 only - Oct 31 2:00 0 S
1066 Rule Edm 1919 only - May 27 2:00 0 S
1067 Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D
1068 Rule Edm 1920 only - Oct lastSun 2:00 0 S
1069 Rule Edm 1921 1923 - Sep lastSun 2:00 0 S
1070 Rule Edm 1942 only - Feb 9 2:00 1:00 W
1071 Rule Edm 1945 only - Sep lastSun 2:00 0 S
1072 Rule Edm 1947 only - Apr lastSun 2:00 1:00 D
1073 Rule Edm 1947 only - Sep lastSun 2:00 0 S
1074 Rule Edm 1967 only - Apr lastSun 2:00 1:00 D
1075 Rule Edm 1967 only - Oct lastSun 2:00 0 S
1076 Rule Edm 1969 only - Apr lastSun 2:00 1:00 D
1077 Rule Edm 1969 only - Oct lastSun 2:00 0 S
1078 Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D
1079 Rule Edm 1972 max - Oct lastSun 2:00 0 S
1080 Rule Edm 1987 max - Apr Sun>=1 2:00 1:00 D
1081 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1082 Zone America/Edmonton -7:33:52 - LMT 1906 Sep
1083 -7:00 Edm M%sT
1086 # British Columbia
1088 # From Paul Eggert (2000-10-02):
1089 # Shanks writes that since 1970 most of this region has been like Vancouver.
1090 # Dawson Creek uses MST. Much of east BC is like Edmonton.
1091 # Matthews and Vincent (1998) write that Creston is like Dawson Creek.
1093 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1094 Rule Vanc 1918 only - Apr 14 2:00 1:00 D
1095 Rule Vanc 1918 only - Oct 31 2:00 0 S
1096 Rule Vanc 1942 only - Feb 9 2:00 1:00 W
1097 Rule Vanc 1945 only - Sep 30 2:00 0 S
1098 Rule Vanc 1946 1986 - Apr lastSun 2:00 1:00 D
1099 Rule Vanc 1946 only - Oct 13 2:00 0 S
1100 Rule Vanc 1947 1961 - Sep lastSun 2:00 0 S
1101 Rule Vanc 1962 max - Oct lastSun 2:00 0 S
1102 Rule Vanc 1987 max - Apr Sun>=1 2:00 1:00 D
1103 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1104 Zone America/Vancouver -8:12:28 - LMT 1884
1105 -8:00 Vanc P%sT
1106 Zone America/Dawson_Creek -8:00:56 - LMT 1884
1107 -8:00 Canada P%sT 1947
1108 -8:00 Vanc P%sT 1972 Aug 30 2:00
1109 -7:00 - MST
1112 # Northwest Territories, Nunavut, Yukon
1114 # From Paul Eggert (1999-10-29):
1115 # Dawson switched to PST in 1973. Inuvik switched to MST in 1979.
1116 # Mathew Englander <mathew@io.org> (1996-10-07) gives the following refs:
1117 # * 1967. Paragraph 28(34)(g) of the Interpretation Act, S.C. 1967-68,
1118 # c. 7 defines Yukon standard time as UTC-9. This is still valid;
1119 # see Interpretation Act, R.S.C. 1985, c. I-21, s. 35(1).
1120 # * C.O. 1973/214 switched Yukon to PST on 1973-10-28 00:00.
1121 # * O.I.C. 1980/02 established DST.
1122 # * O.I.C. 1987/056 changed DST to Apr firstSun 2:00 to Oct lastSun 2:00.
1123 # Shanks says Yukon's 1973-10-28 switch was at 2:00; go with Englander.
1125 # From Rives McDow (1999-09-04):
1126 # Nunavut ... moved ... to incorporate the whole territory into one time zone.
1127 # <a href="http://www.nunatsiaq.com/nunavut/nvt90903_13.html">
1128 # Nunavut moves to single time zone Oct. 31
1129 # </a>
1130 #
1131 # From Antoine Leca (1999-09-06):
1132 # We then need to create a new timezone for the Kitikmeot region of Nunavut
1133 # to differentiate it from the Yellowknife region.
1135 # From Paul Eggert (1999-09-20):
1136 # <a href="http://www.nunavut.com/basicfacts/english/basicfacts_1territory.html">
1137 # Basic Facts: The New Territory
1138 # </a> (1999) reports that Pangnirtung operates on eastern time,
1139 # and that Coral Harbour does not observe DST. We don't know when
1140 # Pangnirtung switched to eastern time; we'll guess 1995.
1141 # We'll ignore the claim about Coral Harbour for now,
1142 # since we have no further info.
1144 # From Rives McDow (1999-11-08):
1145 # On October 31, when the rest of Nunavut went to Central time,
1146 # Pangnirtung wobbled. Here is the result of their wobble:
1147 #
1148 # The following businesses and organizations in Pangnirtung use Central Time:
1149 #
1150 # First Air, Power Corp, Nunavut Construction, Health Center, RCMP,
1151 # Eastern Arctic National Parks, A & D Specialist
1152 #
1153 # The following businesses and organizations in Pangnirtung use Eastern Time:
1154 #
1155 # Hamlet office, All other businesses, Both schools, Airport operator
1156 #
1157 # This has made for an interesting situation there, which warranted the news.
1158 # No one there that I spoke with seems concerned, or has plans to
1159 # change the local methods of keeping time, as it evidently does not
1160 # really interfere with any activities or make things difficult locally.
1161 # They plan to celebrate New Year's turn-over twice, one hour apart,
1162 # so it appears that the situation will last at least that long.
1163 # The Nunavut Intergovernmental Affairs hopes that they will "come to
1164 # their senses", but the locals evidently don't see any problem with
1165 # the current state of affairs.
1167 # From Michaela Rodrigue, writing in the
1168 # <a href="http://www.nunatsiaq.com/archives/nunavut991130/nvt91119_17.html">
1169 # Nunatsiaq News (1999-11-19)</a>:
1170 # Clyde River, Pangnirtung and Sanikiluaq now operate with two time zones,
1171 # central - or Nunavut time - for government offices, and eastern time
1172 # for municipal offices and schools.... Igloolik [was similar but then]
1173 # made the switch to central time on Saturday, Nov. 6.
1175 # From Paul Eggert (2000-10-02):
1176 # Matthews and Vincent (1998) say the following, but we lack histories
1177 # for these potential new Zones.
1178 #
1179 # The Canadian Forces station at Alert uses Eastern Time while the
1180 # handful of residents at the Eureka weather station [in the Central
1181 # zone] skip daylight savings. Baffin Island, which is crossed by the
1182 # Central, Eastern and Atlantic Time zones only uses Eastern Time.
1183 # Gjoa Haven, Taloyoak and Pelly Bay all use Mountain instead of
1184 # Central Time and Southampton Island [in the Central zone] is not
1185 # required to use daylight savings.
1187 # From
1188 # <a href="http://www.nunatsiaq.com/archives/nunavut001130/nvt21110_02.html">
1189 # Nunavut now has two time zones
1190 # </a> (2000-11-10):
1191 # The Nunavut government would allow its employees in Kugluktuk and
1192 # Cambridge Bay to operate on central time year-round, putting them
1193 # one hour behind the rest of Nunavut for six months during the winter.
1194 # At the end of October the two communities had rebelled against
1195 # Nunavut's unified time zone, refusing to shift to eastern time with
1196 # the rest of the territory for the winter. Cambridge Bay remained on
1197 # central time, while Kugluktuk, even farther west, reverted to
1198 # mountain time, which they had used before the advent of Nunavut's
1199 # unified time zone in 1999.
1200 #
1201 # From Rives McDow (2001-01-20), quoting the Nunavut government:
1202 # The preceding decision came into effect at midnight, Saturday Nov 4, 2000.
1204 # From Paul Eggert (2000-12-04):
1205 # Let's just keep track of the official times for now.
1207 # From Rives McDow (2001-03-07):
1208 # The premier of Nunavut has issued a ministerial statement advising
1209 # that effective 2001-04-01, the territory of Nunavut will revert
1210 # back to three time zones (mountain, central, and eastern). Of the
1211 # cities in Nunavut, Coral Harbor is the only one that I know of that
1212 # has said it will not observe dst, staying on EST year round. I'm
1213 # checking for more info, and will get back to you if I come up with
1214 # more.
1215 # [Also see <http://www.nunatsiaq.com/nunavut/nvt10309_06.html> (2001-03-09).]
1217 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1218 Rule NT_YK 1918 only - Apr 14 2:00 1:00 D
1219 Rule NT_YK 1918 only - Oct 27 2:00 0 S
1220 Rule NT_YK 1919 only - May 25 2:00 1:00 D
1221 Rule NT_YK 1919 only - Nov 1 0:00 0 S
1222 Rule NT_YK 1942 only - Feb 9 2:00 1:00 W
1223 Rule NT_YK 1945 only - Sep 30 2:00 0 S
1224 Rule NT_YK 1965 only - Apr lastSun 0:00 2:00 DD
1225 Rule NT_YK 1965 only - Oct lastSun 2:00 0 S
1226 Rule NT_YK 1980 1986 - Apr lastSun 2:00 1:00 D
1227 Rule NT_YK 1980 max - Oct lastSun 2:00 0 S
1228 Rule NT_YK 1987 max - Apr Sun>=1 2:00 1:00 D
1229 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1230 Zone America/Pangnirtung -4:22:56 - LMT 1884
1231 -4:00 NT_YK A%sT 1995 Apr Sun>=1 2:00
1232 -5:00 Canada E%sT 1999 Oct 31 2:00
1233 -6:00 Canada C%sT 2000 Oct 29 2:00
1234 -5:00 Canada E%sT
1235 Zone America/Iqaluit -4:33:52 - LMT 1884 # Frobisher Bay before 1987
1236 -5:00 NT_YK E%sT 1999 Oct 31 2:00
1237 -6:00 Canada C%sT 2000 Oct 29 2:00
1238 -5:00 Canada E%sT
1239 Zone America/Rankin_Inlet -6:08:40 - LMT 1884
1240 -6:00 NT_YK C%sT 2000 Oct 29 2:00
1241 -5:00 - EST 2001 Apr 1 3:00
1242 -6:00 Canada C%sT
1243 Zone America/Cambridge_Bay -7:00:20 - LMT 1884
1244 -7:00 NT_YK M%sT 1999 Oct 31 2:00
1245 -6:00 Canada C%sT 2000 Oct 29 2:00
1246 -5:00 - EST 2000 Nov 5 0:00
1247 -6:00 - CST 2001 Apr 1 3:00
1248 -7:00 Canada M%sT
1249 Zone America/Yellowknife -7:37:24 - LMT 1884
1250 -7:00 NT_YK M%sT
1251 Zone America/Inuvik -8:54:00 - LMT 1884
1252 -8:00 NT_YK P%sT 1979 Apr lastSun 2:00
1253 -7:00 NT_YK M%sT
1254 Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20
1255 -9:00 NT_YK Y%sT 1966 Jul 1 2:00
1256 -8:00 NT_YK P%sT
1257 Zone America/Dawson -9:17:40 - LMT 1900 Aug 20
1258 -9:00 NT_YK Y%sT 1973 Oct 28 0:00
1259 -8:00 NT_YK P%sT
1262 ###############################################################################
1264 # Mexico
1266 # From Paul Eggert (2001-03-05):
1267 # The Investigation and Analysis Service of the
1268 # Mexican Library of Congress (MLoC) has published a
1269 # <a href="http://www.cddhcu.gob.mx/bibliot/publica/inveyana/polisoc/horver/">
1270 # history of Mexican local time (in Spanish)
1271 # </a>.
1272 #
1273 # Here are the discrepancies between Shanks and the MLoC.
1274 # (In all cases we go with the MLoC.)
1275 # Shanks reports that Baja was at -8:00 in 1922/1923.
1276 # Shanks says the 1930 transition in Baja was 1930-11-16.
1277 # Shanks reports no DST during summer 1931.
1278 # Shanks reports a transition at 1032-03-30 23:00, not 1932-04-01.
1279 # Shanks does not report transitions for Baja in 1945 or 1948.
1280 # Shanks reports southern Mexico transitions on 1981-12-01, not 12-23.
1281 # Shanks says Quintana Roo switched to -6:00 on 1982-12-02, and to -5:00
1282 # on 1997-10-26 at 02:00.
1284 # From Gwillim Law (2001-02-20):
1285 # There are some other discrepancies between the Decrees page and the
1286 # tz database. I think they can best be explained by supposing that
1287 # the researchers who prepared the Decrees page failed to find some of
1288 # the relevant documents.
1290 # From Paul Eggert (2000-07-26):
1291 # Shanks gives 1942-04-01 instead of 1942-04-24, and omits the 1981
1292 # and 1988 DST experiments. Go with spin.com.mx.
1294 # From Alan Perry <alan.perry@eng.sun.com> (1996-02-15):
1295 # A guy from our Mexico subsidiary finally found the Presidential Decree
1296 # outlining the timezone changes in Mexico.
1297 #
1298 # ------------- Begin Forwarded Message -------------
1299 #
1300 # I finally got my hands on the Official Presidential Decree that sets up the
1301 # rules for the DST changes. The rules are:
1302 #
1303 # 1. The country is divided in 3 timezones:
1304 # - Baja California Norte (the Mexico/BajaNorte TZ)
1305 # - Baja California Sur, Nayarit, Sinaloa and Sonora (the Mexico/BajaSur TZ)
1306 # - The rest of the country (the Mexico/General TZ)
1307 #
1308 # 2. From the first Sunday in April at 2:00 AM to the last Sunday in October
1309 # at 2:00 AM, the times in each zone are as follows:
1310 # BajaNorte: GMT+7
1311 # BajaSur: GMT+6
1312 # General: GMT+5
1313 #
1314 # 3. The rest of the year, the times are as follows:
1315 # BajaNorte: GMT+8
1316 # BajaSur: GMT+7
1317 # General: GMT+6
1318 #
1319 # The Decree was published in Mexico's Official Newspaper on January 4th.
1320 #
1321 # -------------- End Forwarded Message --------------
1322 # From Paul Eggert (1996-06-12):
1323 # For an English translation of the decree, see
1324 # <a href="http://mexico-travel.com/extra/timezone_eng.html">
1325 # ``Diario Oficial: Time Zone Changeover'' (1996-01-04).
1326 # </a>
1328 # From Rives McDow (1998-10-08):
1329 # The State of Quintana Roo has reverted back to central STD and DST times
1330 # (i.e. UTC -0600 and -0500 as of 1998-08-02).
1332 # From Rives McDow (2000-01-10):
1333 # Effective April 4, 1999 at 2:00 AM local time, Sonora changed to the time
1334 # zone 5 hours from the International Date Line, and will not observe daylight
1335 # savings time so as to stay on the same time zone as the southern part of
1336 # Arizona year round.
1338 # From Jesper Norgaard, translating
1339 # <http://www.reforma.com/nacional/articulo/064327/> (2001-01-17):
1340 # In Oaxaca, the 55.000 teachers from the Section 22 of the National
1341 # Syndicate of Education Workers, refuse to apply daylight saving each
1342 # year, so that the more than 10,000 schools work at normal hour the
1343 # whole year.
1345 # From Gwillim Law (2001-01-19):
1346 # <http://www.reforma.com/negocios_y_dinero/articulo/064481/> ... says
1347 # (translated):...
1348 # January 17, 2000 - The Energy Secretary, Ernesto Martens, announced
1349 # that Summer Time will be reduced from seven to five months, starting
1350 # this year....
1351 # <http://www.publico.com.mx/scripts/texto3.asp?action=pagina&pag=21&pos=p&secc=naci&date=01/17/2001>
1352 # [translated], says "summer time will ... take effect on the first Sunday
1353 # in May, and end on the last Sunday of September.
1355 # From Arthur David Olson (2001-01-25):
1356 # The 2001-01-24 traditional Washington Post contained the page one
1357 # story "Timely Issue Divides Mexicans."...
1358 # http://www.washingtonpost.com/wp-dyn/articles/A37383-2001Jan23.html
1359 # ... Mexico City Mayor Lopez Obrador "...is threatening to keep
1360 # Mexico City and its 20 million residents on a different time than
1361 # the rest of the country..." In particular, Lopez Obrador would abolish
1362 # observation of Daylight Saving Time.
1364 # <a href="http://www.conae.gob.mx/ahorro/decretohorver2001.html#decre">
1365 # Official statute published by the Energy Department
1366 # </a> (2001-02-01) shows Baja and Chihauhua as still using US DST rules,
1367 # and Sonora with no DST. This was reported by Jesper Norgaard (2001-02-03).
1369 # From Paul Eggert (2001-03-03):
1370 #
1371 # <a href="http://www.latimes.com/news/nation/20010303/t000018766.html">
1372 # James F. Smith writes in today's LA Times
1373 # </a>
1374 # * Sonora will continue to observe standard time.
1375 # * Last week Mexico City's mayor Andres Manuel Lopez Obrador decreed that
1376 # the Federal District will not adopt DST.
1377 # * 4 of 16 district leaders announced they'll ignore the decree.
1378 # * The decree does not affect federal-controlled facilities including
1379 # the airport, banks, hospitals, and schools.
1380 #
1381 # For now we'll assume that the Federal District will bow to federal rules.
1383 # From Jesper Norgaard (2001-04-01):
1384 # I found some references to the Mexican application of daylight
1385 # saving, which modifies what I had already sent you, stating earlier
1386 # that a number of northern Mexican states would go on daylight
1387 # saving. The modification reverts this to only cover Baja California
1388 # (Norte), while all other states (except Sonora, who has no daylight
1389 # saving all year) will follow the original decree of president
1390 # Vicente Fox, starting daylight saving May 6, 2001 and ending
1391 # September 30, 2001.
1392 # References: "Diario de Monterrey" <www.diariodemonterrey.com/index.asp>
1393 # Palabra <http://palabra.infosel.com/010331/primera/ppri3101.pdf> (2001-03-31)
1395 # From Reuters (2001-09-04):
1396 # Mexico's Supreme Court on Tuesday declared that daylight savings was
1397 # unconstitutional in Mexico City, creating the possibility the
1398 # capital will be in a different time zone from the rest of the nation
1399 # next year.... The Supreme Court's ruling takes effect at 2:00
1400 # a.m. (0800 GMT) on Sept. 30, when Mexico is scheduled to revert to
1401 # standard time. "This is so residents of the Federal District are not
1402 # subject to unexpected time changes," a statement from the court said.
1404 # From Jesper Norgaard Welen (2002-03-12):
1405 # ... consulting my local grocery store(!) and my coworkers, they all insisted
1406 # that a new decision had been made to reinstate US style DST in Mexico....
1407 # http://www.conae.gob.mx/ahorro/horaver2001_m1_2002.html (2002-02-20)
1408 # confirms this. Sonora as usual is the only state where DST is not applied.
1410 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1411 Rule Mexico 1939 only - Feb 5 0:00 1:00 D
1412 Rule Mexico 1939 only - Jun 25 0:00 0 S
1413 Rule Mexico 1940 only - Dec 9 0:00 1:00 D
1414 Rule Mexico 1941 only - Apr 1 0:00 0 S
1415 Rule Mexico 1943 only - Dec 16 0:00 1:00 W
1416 Rule Mexico 1944 only - May 1 0:00 0 S
1417 Rule Mexico 1950 only - Feb 12 0:00 1:00 D
1418 Rule Mexico 1950 only - Jul 30 0:00 0 S
1419 Rule Mexico 1996 2000 - Apr Sun>=1 2:00 1:00 D
1420 Rule Mexico 1996 2000 - Oct lastSun 2:00 0 S
1421 Rule Mexico 2001 only - May Sun>=1 2:00 1:00 D
1422 Rule Mexico 2001 only - Sep lastSun 2:00 0 S
1423 Rule Mexico 2002 max - Apr Sun>=1 2:00 1:00 D
1424 Rule Mexico 2002 max - Oct lastSun 2:00 0 S
1425 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1426 # Quintana Roo
1427 Zone America/Cancun -5:47:04 - LMT 1922 Jan 1 0:12:56
1428 -6:00 - CST 1981 Dec 23
1429 -5:00 Mexico E%sT 1998 Aug 2 2:00
1430 -6:00 Mexico C%sT
1431 # Campeche, Yucatan
1432 Zone America/Merida -5:58:28 - LMT 1922 Jan 1 0:01:32
1433 -6:00 - CST 1981 Dec 23
1434 -5:00 - EST 1982 Dec 2
1435 -6:00 Mexico C%sT
1436 # Coahuila, Durango, Nuevo Leon, Tamaulipas
1437 Zone America/Monterrey -6:41:16 - LMT 1921 Dec 31 23:18:44
1438 -6:00 - CST 1988
1439 -6:00 US C%sT 1989
1440 -6:00 Mexico C%sT
1441 # Central Mexico
1442 Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 0:23:24
1443 -7:00 - MST 1927 Jun 10 23:00
1444 -6:00 - CST 1930 Nov 15
1445 -7:00 - MST 1931 May 1 23:00
1446 -6:00 - CST 1931 Oct
1447 -7:00 - MST 1932 Apr 1
1448 -6:00 Mexico C%sT 2001 Sep 30 02:00
1449 -6:00 - CST 2002 Feb 20
1450 -6:00 Mexico C%sT
1451 # Chihuahua
1452 Zone America/Chihuahua -7:04:20 - LMT 1921 Dec 31 23:55:40
1453 -7:00 - MST 1927 Jun 10 23:00
1454 -6:00 - CST 1930 Nov 15
1455 -7:00 - MST 1931 May 1 23:00
1456 -6:00 - CST 1931 Oct
1457 -7:00 - MST 1932 Apr 1
1458 -6:00 - CST 1996
1459 -6:00 Mexico C%sT 1998
1460 -6:00 - CST 1998 Apr Sun>=1 3:00
1461 -7:00 Mexico M%sT
1462 # Sonora
1463 Zone America/Hermosillo -7:23:52 - LMT 1921 Dec 31 23:36:08
1464 -7:00 - MST 1927 Jun 10 23:00
1465 -6:00 - CST 1930 Nov 15
1466 -7:00 - MST 1931 May 1 23:00
1467 -6:00 - CST 1931 Oct
1468 -7:00 - MST 1932 Apr 1
1469 -6:00 - CST 1942 Apr 24
1470 -7:00 - MST 1949 Jan 14
1471 -8:00 - PST 1970
1472 -7:00 Mexico M%sT 1999
1473 -7:00 - MST
1474 # Baja California Sur, Nayarit, Sinaloa
1475 Zone America/Mazatlan -7:05:40 - LMT 1921 Dec 31 23:54:20
1476 -7:00 - MST 1927 Jun 10 23:00
1477 -6:00 - CST 1930 Nov 15
1478 -7:00 - MST 1931 May 1 23:00
1479 -6:00 - CST 1931 Oct
1480 -7:00 - MST 1932 Apr 1
1481 -6:00 - CST 1942 Apr 24
1482 -7:00 - MST 1949 Jan 14
1483 -8:00 - PST 1970
1484 -7:00 Mexico M%sT
1485 # Baja California
1486 Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 0:11:56
1487 -7:00 - MST 1924
1488 -8:00 - PST 1927 Jun 10 23:00
1489 -7:00 - MST 1930 Nov 15
1490 -8:00 - PST 1931 Apr 1
1491 -8:00 1:00 PDT 1931 Sep 30
1492 -8:00 - PST 1942 Apr 24
1493 -8:00 1:00 PWT 1945 Nov 12
1494 -8:00 - PST 1948 Apr 5
1495 -8:00 1:00 PDT 1949 Jan 14
1496 -8:00 - PST 1954
1497 -8:00 CA P%sT 1961
1498 -8:00 - PST 1976
1499 -8:00 US P%sT 1996
1500 -8:00 Mexico P%sT 2001
1501 -8:00 US P%sT 2002 Feb 20
1502 -8:00 Mexico P%sT
1503 # From Paul Eggert (2001-03-05):
1504 # Formerly there was an America/Ensenada zone, which differed from
1505 # America/Tijuana only in that it did not observe DST from 1976
1506 # through 1995. This was as per Shanks. However, Guy Harris reports
1507 # that the 1987 OAG says "Only Ensenada, Mexicale, San Felipe and
1508 # Tijuana observe DST," which contradicts Shanks but does imply that
1509 # DST-observance was a town-by-town matter back then. This concerns
1510 # data after 1970 so most likely there should be at least one Zone
1511 # other than America/Tijuana for Baja, but it's not clear yet what its
1512 # name or contents should be.
1513 #
1514 # Revillagigedo Is
1515 # no information
1517 ###############################################################################
1519 # Anguilla
1520 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1521 Zone America/Anguilla -4:12:16 - LMT 1912 Mar 2
1522 -4:00 - AST
1524 # Antigua and Barbuda
1525 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1526 Zone America/Antigua -4:07:12 - LMT 1912 Mar 2
1527 -5:00 - EST 1951
1528 -4:00 - AST
1530 # Bahamas
1531 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1532 Rule Bahamas 1964 max - Oct lastSun 2:00 0 S
1533 Rule Bahamas 1964 1986 - Apr lastSun 2:00 1:00 D
1534 Rule Bahamas 1987 max - Apr Sun>=1 2:00 1:00 D
1535 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1536 Zone America/Nassau -5:09:24 - LMT 1912 Mar 2
1537 -5:00 Bahamas E%sT
1539 # Barbados
1540 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1541 Rule Barb 1977 only - Jun 12 2:00 1:00 D
1542 Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S
1543 Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D
1544 Rule Barb 1979 only - Sep 30 2:00 0 S
1545 Rule Barb 1980 only - Sep 25 2:00 0 S
1546 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1547 Zone America/Barbados -3:58:28 - LMT 1924 # Bridgetown
1548 -3:58:28 - BMT 1932 # Bridgetown Mean Time
1549 -4:00 Barb A%sT
1551 # Belize
1552 # Whitman entirely disagrees with Shanks; go with Shanks.
1553 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1554 Rule Belize 1918 1942 - Oct Sun>=2 0:00 0:30 HD
1555 Rule Belize 1919 1943 - Feb Sun>=9 0:00 0 S
1556 Rule Belize 1973 only - Dec 5 0:00 1:00 D
1557 Rule Belize 1974 only - Feb 9 0:00 0 S
1558 Rule Belize 1982 only - Dec 18 0:00 1:00 D
1559 Rule Belize 1983 only - Feb 12 0:00 0 S
1560 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1561 Zone America/Belize -5:52:48 - LMT 1912 Apr
1562 -6:00 Belize C%sT
1564 # Bermuda
1565 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1566 Zone Atlantic/Bermuda -4:19:04 - LMT 1930 Jan 1 2:00 # Hamilton
1567 -4:00 - AST 1974 Apr 28 2:00
1568 -4:00 Bahamas A%sT
1570 # Cayman Is
1571 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1572 Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown
1573 -5:07:12 - KMT 1912 Feb # Kingston Mean Time
1574 -5:00 - EST
1576 # Costa Rica
1577 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1578 Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D
1579 Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S
1580 Rule CR 1991 1992 - Jan Sat>=15 0:00 1:00 D
1581 # IATA SSIM (1991-09) says the following was at 1:00; go with Shanks.
1582 Rule CR 1991 only - Jul 1 0:00 0 S
1583 Rule CR 1992 only - Mar 15 0:00 0 S
1584 # There are too many San Joses elsewhere, so we'll use `Costa Rica'.
1585 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1586 Zone America/Costa_Rica -5:36:20 - LMT 1890 # San Jose
1587 -5:36:20 - SJMT 1921 Jan 15 # San Jose Mean Time
1588 -6:00 CR C%sT
1589 # Coco
1590 # no information; probably like America/Costa_Rica
1592 # Cuba
1594 # From Arthur David Olson (1999-03-29):
1595 # The 1999-03-28 exhibition baseball game held in Havana, Cuba, between
1596 # the Cuban National Team and the Baltimore Orioles was carried live on
1597 # the Orioles Radio Network, including affiliate WTOP in Washington, DC.
1598 # During the game, play-by-play announcer Jim Hunter noted that
1599 # "We'll be losing two hours of sleep...Cuba switched to Daylight Saving
1600 # Time today." (The "two hour" remark referred to losing one hour of
1601 # sleep on 1999-03-28--when the announcers were in Cuba as it switched
1602 # to DST--and one more hour on 1999-04-04--when the announcers will have
1603 # returned to Baltimore, which switches on that date.)
1605 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1606 Rule Cuba 1928 only - Jun 10 0:00 1:00 D
1607 Rule Cuba 1928 only - Oct 10 0:00 0 S
1608 Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D
1609 Rule Cuba 1940 1942 - Sep Sun>=1 0:00 0 S
1610 Rule Cuba 1945 1946 - Jun Sun>=1 0:00 1:00 D
1611 Rule Cuba 1945 1946 - Sep Sun>=1 0:00 0 S
1612 Rule Cuba 1965 only - Jun 1 0:00 1:00 D
1613 Rule Cuba 1965 only - Sep 30 0:00 0 S
1614 Rule Cuba 1966 only - May 29 0:00 1:00 D
1615 Rule Cuba 1966 only - Oct 2 0:00 0 S
1616 Rule Cuba 1967 only - Apr 8 0:00 1:00 D
1617 Rule Cuba 1967 1968 - Sep Sun>=8 0:00 0 S
1618 Rule Cuba 1968 only - Apr 14 0:00 1:00 D
1619 Rule Cuba 1969 1977 - Apr lastSun 0:00 1:00 D
1620 Rule Cuba 1969 1971 - Oct lastSun 0:00 0 S
1621 Rule Cuba 1972 1974 - Oct 8 0:00 0 S
1622 Rule Cuba 1975 1977 - Oct lastSun 0:00 0 S
1623 Rule Cuba 1978 only - May 7 0:00 1:00 D
1624 Rule Cuba 1978 1990 - Oct Sun>=8 0:00 0 S
1625 Rule Cuba 1979 1980 - Mar Sun>=15 0:00 1:00 D
1626 Rule Cuba 1981 1985 - May Sun>=5 0:00 1:00 D
1627 Rule Cuba 1986 1989 - Mar Sun>=14 0:00 1:00 D
1628 Rule Cuba 1990 1997 - Apr Sun>=1 0:00 1:00 D
1629 Rule Cuba 1991 1995 - Oct Sun>=8 0:00s 0 S
1630 Rule Cuba 1996 only - Oct 6 0:00s 0 S
1631 Rule Cuba 1997 only - Oct 12 0:00s 0 S
1632 Rule Cuba 1998 1999 - Mar lastSun 0:00s 1:00 D
1633 Rule Cuba 1998 max - Oct lastSun 0:00s 0 S
1634 Rule Cuba 2000 max - Apr Sun>=1 0:00s 1:00 D
1636 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1637 Zone America/Havana -5:29:28 - LMT 1890
1638 -5:29:36 - HMT 1925 Jul 19 12:00 # Havana MT
1639 -5:00 Cuba C%sT
1641 # Dominica
1642 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1643 Zone America/Dominica -4:05:36 - LMT 1911 Jul 1 0:01 # Roseau
1644 -4:00 - AST
1646 # Dominican Republic
1648 # From Steffen Thorsen (2000-10-30):
1649 # Enrique Morales reported to me that the Dominican Republic has changed the
1650 # time zone to Eastern Standard Time as of Sunday 29 at 2 am....
1651 # http://www.listin.com.do/antes/261000/republica/princi.html
1653 # From Paul Eggert (2000-12-04):
1654 # That URL (2000-10-26, in Spanish) says they planned to use US-style DST.
1656 # From Rives McDow (2000-12-01):
1657 # Dominican Republic changed its mind and presidential decree on Tuesday,
1658 # November 28, 2000, with a new decree. On Sunday, December 3 at 1:00 AM the
1659 # Dominican Republic will be reverting to 8 hours from the International Date
1660 # Line, and will not be using DST in the foreseeable future. The reason they
1661 # decided to use DST was to be in synch with Puerto Rico, who was also going
1662 # to implement DST. When Puerto Rico didn't implement DST, the president
1663 # decided to revert.
1666 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1667 Rule DR 1966 only - Oct 30 0:00 1:00 D
1668 Rule DR 1967 only - Feb 28 0:00 0 S
1669 Rule DR 1969 1973 - Oct lastSun 0:00 0:30 HD
1670 Rule DR 1970 only - Feb 21 0:00 0 S
1671 Rule DR 1971 only - Jan 20 0:00 0 S
1672 Rule DR 1972 1974 - Jan 21 0:00 0 S
1673 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1674 Zone America/Santo_Domingo -4:39:36 - LMT 1890
1675 -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT
1676 -5:00 DR E%sT 1974 Oct 27
1677 -4:00 - AST 2000 Oct 29 02:00
1678 -5:00 US E%sT 2000 Dec 3 01:00
1679 -4:00 - AST
1681 # El Salvador
1682 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1683 Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D
1684 Rule Salv 1987 1988 - Sep lastSun 0:00 0 S
1685 # There are too many San Salvadors elsewhere, so we'll use `El Salvador'.
1686 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1687 Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador
1688 -6:00 Salv C%sT
1690 # Grenada
1691 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1692 Zone America/Grenada -4:07:00 - LMT 1911 Jul # St George's
1693 -4:00 - AST
1695 # Guadeloupe
1696 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1697 Zone America/Guadeloupe -4:06:08 - LMT 1911 Jun 8 # Pointe a Pitre
1698 -4:00 - AST
1700 # Guatemala
1701 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1702 Rule Guat 1973 only - Nov 25 0:00 1:00 D
1703 Rule Guat 1974 only - Feb 24 0:00 0 S
1704 Rule Guat 1983 only - May 21 0:00 1:00 D
1705 Rule Guat 1983 only - Sep 22 0:00 0 S
1706 Rule Guat 1991 only - Mar 23 0:00 1:00 D
1707 Rule Guat 1991 only - Sep 7 0:00 0 S
1708 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1709 Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5
1710 -6:00 Guat C%sT
1712 # Haiti
1713 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1714 Rule Haiti 1983 only - May 8 0:00 1:00 D
1715 Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D
1716 Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S
1717 # Shanks says AT is 2:00, but IATA SSIM (1991/1997) says 1:00s. Go with IATA.
1718 Rule Haiti 1988 1997 - Apr Sun>=1 1:00s 1:00 D
1719 Rule Haiti 1988 1997 - Oct lastSun 1:00s 0 S
1720 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1721 Zone America/Port-au-Prince -4:49:20 - LMT 1890
1722 -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT
1723 -5:00 Haiti E%sT
1725 # Honduras
1726 # Shanks says 1921 Jan 1; go with Whitman's more precise Apr 1.
1727 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1728 Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr
1729 -6:00 Salv C%sT
1730 #
1731 # Great Swan I ceded by US to Honduras in 1972
1733 # Jamaica
1735 # From Bob Devine (1988-01-28):
1736 # Follows US rules.
1738 # From U. S. Naval Observatory (1989-01-19):
1739 # JAMAICA 5 H BEHIND UTC
1741 # From Shanks:
1742 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1743 Zone America/Jamaica -5:07:12 - LMT 1890 # Kingston
1744 -5:07:12 - KMT 1912 Feb # Kingston Mean Time
1745 -5:00 - EST 1974 Apr 28 2:00
1746 -5:00 US E%sT 1984
1747 -5:00 - EST
1749 # Martinique
1750 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1751 Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France
1752 -4:04:20 - FFMT 1911 May # Fort-de-France MT
1753 -4:00 - AST 1980 Apr 6
1754 -4:00 1:00 ADT 1980 Sep 28
1755 -4:00 - AST
1757 # Montserrat
1758 # From Paul Eggert (1997-08-31):
1759 # Recent volcanic eruptions have forced evacuation of Plymouth, the capital.
1760 # Luckily, Olveston, the current de facto capital, has the same longitude.
1761 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1762 Zone America/Montserrat -4:08:52 - LMT 1911 Jul 1 0:01 # Olveston
1763 -4:00 - AST
1765 # Nicaragua
1766 #
1767 # From Steffen Thorsen (1998-12-29):
1768 # Nicaragua seems to be back at -6:00 but I have not been able to find when
1769 # they changed from -5:00.
1770 #
1771 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1772 Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D
1773 Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S
1774 Rule Nic 1992 only - Jan 1 4:00 1:00 D
1775 Rule Nic 1992 only - Sep 24 0:00 0 S
1776 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1777 Zone America/Managua -5:45:08 - LMT 1890
1778 -5:45:12 - MMT 1934 Jun 23 # Managua Mean Time?
1779 -6:00 - CST 1973 May
1780 -5:00 - EST 1975 Feb 16
1781 -6:00 Nic C%sT 1993 Jan 1 4:00
1782 -5:00 - EST 1998 Dec
1783 -6:00 - CST
1785 # Panama
1786 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1787 Zone America/Panama -5:18:08 - LMT 1890
1788 -5:19:36 - CMT 1908 Apr 22 # Colon Mean Time
1789 -5:00 - EST
1791 # Puerto Rico
1792 # There are too many San Juans elsewhere, so we'll use `Puerto_Rico'.
1793 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1794 Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan
1795 -4:00 - AST 1942 May 3
1796 -4:00 1:00 AWT 1945 Sep 30 2:00
1797 -4:00 - AST
1799 # St Kitts-Nevis
1800 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1801 Zone America/St_Kitts -4:10:52 - LMT 1912 Mar 2 # Basseterre
1802 -4:00 - AST
1804 # St Lucia
1805 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1806 Zone America/St_Lucia -4:04:00 - LMT 1890 # Castries
1807 -4:04:00 - CMT 1912 # Castries Mean Time
1808 -4:00 - AST
1810 # St Pierre and Miquelon
1811 # There are too many St Pierres elsewhere, so we'll use `Miquelon'.
1812 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1813 Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre
1814 -4:00 - AST 1980 May
1815 -3:00 Mont PM%sT # Pierre & Miquelon Time
1817 # St Vincent and the Grenadines
1818 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1819 Zone America/St_Vincent -4:04:56 - LMT 1890 # Kingstown
1820 -4:04:56 - KMT 1912 # Kingstown Mean Time
1821 -4:00 - AST
1823 # Turks and Caicos
1824 # From Paul Eggert (1998-08-06):
1825 # Shanks says they use US DST rules, but IATA SSIM (1991/1998)
1826 # says they switch at midnight. Go with IATA SSIM.
1827 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1828 Rule TC 1979 1986 - Apr lastSun 0:00 1:00 D
1829 Rule TC 1979 max - Oct lastSun 0:00 0 S
1830 Rule TC 1987 max - Apr Sun>=1 0:00 1:00 D
1831 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1832 Zone America/Grand_Turk -4:44:32 - LMT 1890
1833 -5:07:12 - KMT 1912 Feb # Kingston Mean Time
1834 -5:00 TC E%sT
1836 # British Virgin Is
1837 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1838 Zone America/Tortola -4:18:28 - LMT 1911 Jul # Road Town
1839 -4:00 - AST
1841 # Virgin Is
1842 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1843 Zone America/St_Thomas -4:19:44 - LMT 1911 Jul # Charlotte Amalie
1844 -4:00 - AST