| blob | 29bba4f1d1d943aa2d7b0f510036f691537a1398 |
1 # @(#)northamerica 7.61
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 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
92 Rule US 1918 1919 - Mar lastSun 2:00 1:00 D
93 Rule US 1918 1919 - Oct lastSun 2:00 0 S
94 Rule US 1942 only - Feb 9 2:00 1:00 W # War
95 Rule US 1945 only - Aug 14 23:00u 1:00 P # Peace
96 Rule US 1945 only - Sep 30 2:00 0 S
97 Rule US 1967 max - Oct lastSun 2:00 0 S
98 Rule US 1967 1973 - Apr lastSun 2:00 1:00 D
99 Rule US 1974 only - Jan 6 2:00 1:00 D
100 Rule US 1975 only - Feb 23 2:00 1:00 D
101 Rule US 1976 1986 - Apr lastSun 2:00 1:00 D
102 Rule US 1987 max - Apr Sun>=1 2:00 1:00 D
103 # <a href="http://thomas.loc.gov/cgi-bin/bdquery/z?d106:h.r.00177:">
104 # H.R.177
105 # </a> (introduced 1999-01-06) would change April to March in the above rule.
107 # From Bob Devine (1988-01-28):
108 # ...Alaska (and Hawaii) had the timezone names changed in 1967.
109 # old new
110 # Pacific Standard Time(PST) -same-
111 # Yukon Standard Time(YST) -same-
112 # Central Alaska S.T. (CAT) Alaska-Hawaii St[an]dard Time (AHST)
113 # Nome Standard Time (NT) Bering Standard Time (BST)
114 #
115 # ...Alaska's timezone lines were redrawn in 1983 to give only 2 tz.
116 # The YST zone now covers nearly all of the state, AHST just part
117 # of the Aleutian islands. No DST.
119 # From Paul Eggert (1995-12-19):
120 # The tables below use `NST', not `NT', for Nome Standard Time.
121 # I invented `CAWT' for Central Alaska War Time.
123 # From U. S. Naval Observatory (1989-01-19):
124 # USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON
125 # USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30
126 # USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON
127 # USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30
128 # USA MOUNTAIN 7 H BEHIND UTC DENVER
129 # USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30
130 # USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO
131 # USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30
132 # USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST)
133 # USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT)
134 # USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W
135 # USA - " - 9 H BEHIND UTC APR 3 - OCT 30
136 # USA HAWAII 10 H BEHIND UTC
137 # USA BERING 11 H BEHIND UTC SAMOA, MIDWAY
139 # From Arthur David Olson (1989-01-21):
140 # The above dates are for 1988.
141 # Note the "AKST" and "AKDT" abbreviations, the claim that there's
142 # no DST in Samoa, and the claim that there is DST in Alaska and the
143 # Aleutians.
145 # From Arthur David Olson (1988-02-13):
146 # Legal standard time zone names, from United States Code (1982 Edition and
147 # Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names
148 # up to 1967-04-01 (when most provisions of the Uniform Time Act of 1966
149 # took effect), as explained in sections 263 and 261:
150 # (none)
151 # United States standard eastern time
152 # United States standard mountain time
153 # United States standard central time
154 # United States standard Pacific time
155 # (none)
156 # United States standard Alaska time
157 # (none)
158 # Next, names from 1967-04-01 until 1983-11-30 (the date for
159 # public law 98-181):
160 # Atlantic standard time
161 # eastern standard time
162 # central standard time
163 # mountain standard time
164 # Pacific standard time
165 # Yukon standard time
166 # Alaska-Hawaii standard time
167 # Bering standard time
168 # And after 1983-11-30:
169 # Atlantic standard time
170 # eastern standard time
171 # central standard time
172 # mountain standard time
173 # Pacific standard time
174 # Alaska standard time
175 # Hawaii-Aleutian standard time
176 # Samoa standard time
177 # The law doesn't give abbreviations.
178 #
179 # From Paul Eggert (1995-12-19):
180 # Shanks uses 1983-10-30, not 1983-11-30, for the 1983 transitions.
181 # Go with Shanks.
182 #
183 # From Paul Eggert (2000-01-08), following a heads-up from Rives McDow:
184 # Public law 106-564 (2000-12-23) introduced the abbreviation
185 # "Chamorro Standard Time" for time in Guam and the Northern Marianas.
186 # See the file "australasia".
189 # US eastern time, represented by New York
191 # Connecticut, Delaware, District of Columbia, most of Florida,
192 # Georgia, far southeastern Indiana, eastern Kentucky, Maine,
193 # Maryland, Massachusetts, New Hampshire, New Jersey, New York, North
194 # Carolina, Ohio, Pennsylvania, Rhode Island, South Carolina, eastern
195 # Tennessee, Vermont, Virginia, West Virginia
197 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
198 Rule NYC 1920 only - Mar lastSun 2:00 1:00 D
199 Rule NYC 1920 only - Oct lastSun 2:00 0 S
200 Rule NYC 1921 1966 - Apr lastSun 2:00 1:00 D
201 Rule NYC 1921 1954 - Sep lastSun 2:00 0 S
202 Rule NYC 1955 1966 - Oct lastSun 2:00 0 S
203 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
204 Zone America/New_York -4:56:02 - LMT 1883 Nov 18 12:00
205 -5:00 US E%sT 1920
206 -5:00 NYC E%sT 1942
207 -5:00 US E%sT 1946
208 -5:00 NYC E%sT 1967
209 -5:00 US E%sT
211 # US central time, represented by Chicago
213 # Alabama, Arkansas, Florida panhandle, Illinois, western Indiana
214 # corners, Iowa, most of Kansas, western Kentucky, Louisiana,
215 # Minnesota, Mississippi, Missouri, eastern Nebraska, eastern North
216 # Dakota, Oklahoma, eastern South Dakota, western Tennessee, most of
217 # Texas, Wisconsin
219 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
220 Rule Chicago 1920 only - Jun 13 2:00 1:00 D
221 Rule Chicago 1920 1921 - Oct lastSun 2:00 0 S
222 Rule Chicago 1921 only - Mar lastSun 2:00 1:00 D
223 Rule Chicago 1922 1966 - Apr lastSun 2:00 1:00 D
224 Rule Chicago 1922 1954 - Sep lastSun 2:00 0 S
225 Rule Chicago 1955 1966 - Oct lastSun 2:00 0 S
226 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
227 Zone America/Chicago -5:50:36 - LMT 1883 Nov 18 12:00
228 -6:00 US C%sT 1920
229 -6:00 Chicago C%sT 1936 Mar 1 2:00
230 -5:00 - EST 1936 Nov 15 2:00
231 -6:00 Chicago C%sT 1942
232 -6:00 US C%sT 1946
233 -6:00 Chicago C%sT 1967
234 -6:00 US C%sT
235 # Oliver County, ND switched from mountain to central time on 1992-10-25.
236 Zone America/North_Dakota/Center -6:45:12 - LMT 1883 Nov 18 12:00
237 -7:00 US M%sT 1992 Oct 25 02:00
238 -6:00 US C%sT
240 # US mountain time, represented by Denver
241 #
242 # Colorado, southern Idaho, far western Kansas, Montana, western
243 # Nebraska, Nevada border (Jackpot, Owyhee, and Mountain City),
244 # New Mexico, southwestern North Dakota, far eastern Oregon,
245 # western South Dakota, far western Texas (El Paso County, Hudspeth County,
246 # and Pine Springs and Nickel Creek in Culberson County), Utah, Wyoming
247 #
248 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
249 Rule Denver 1920 1921 - Mar lastSun 2:00 1:00 D
250 Rule Denver 1920 only - Oct lastSun 2:00 0 S
251 Rule Denver 1921 only - May 22 2:00 0 S
252 Rule Denver 1965 1966 - Apr lastSun 2:00 1:00 D
253 Rule Denver 1965 1966 - Oct lastSun 2:00 0 S
254 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
255 Zone America/Denver -6:59:56 - LMT 1883 Nov 18 12:00
256 -7:00 US M%sT 1920
257 -7:00 Denver M%sT 1942
258 -7:00 US M%sT 1946
259 -7:00 Denver M%sT 1967
260 -7:00 US M%sT
262 # US Pacific time, represented by Los Angeles
263 #
264 # California, northern Idaho, most of Nevada, most of Oregon, and Washington
265 #
266 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
267 Rule CA 1948 only - Mar 14 2:00 1:00 D
268 Rule CA 1949 only - Jan 1 2:00 0 S
269 Rule CA 1950 1966 - Apr lastSun 2:00 1:00 D
270 Rule CA 1950 1961 - Sep lastSun 2:00 0 S
271 Rule CA 1962 1966 - Oct lastSun 2:00 0 S
272 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
273 Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 12:00
274 -8:00 US P%sT 1946
275 -8:00 CA P%sT 1967
276 -8:00 US P%sT
278 # Alaska
279 # AK%sT is the modern abbreviation for -9:00 per USNO.
280 #
281 # From Paul Eggert (2001-05-30):
282 # Howse writes that Alaska switched from the Julian to the Gregorian calendar,
283 # and from east-of-GMT to west-of-GMT days, when the US bought it from Russia.
284 # This was on 1867-10-18, a Friday; the previous day was 1867-10-06 Julian,
285 # also a Friday. Include only the time zone part of this transition,
286 # ignoring the switch from Julian to Gregorian, since we can't represent
287 # the Julian calendar.
288 #
289 # As far as we know, none of the exact locations mentioned below were
290 # permanently inhabited in 1867 by anyone using either calendar.
291 # (Yakutat was colonized by the Russians in 1799, but the settlement
292 # was destroyed in 1805 by a Yakutat-kon war party.) However, there
293 # were nearby inhabitants in some cases and for our purposes perhaps
294 # it's best to simply use the official transition.
295 #
296 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
297 Zone America/Juneau 15:02:19 - LMT 1867 Oct 18
298 -8:57:41 - LMT 1900 Aug 20 12:00
299 -8:00 - PST 1942
300 -8:00 US P%sT 1946
301 -8:00 - PST 1969
302 -8:00 US P%sT 1983 Oct 30 2:00
303 -9:00 US AK%sT
304 Zone America/Yakutat 14:41:05 - LMT 1867 Oct 18
305 -9:18:55 - LMT 1900 Aug 20 12:00
306 -9:00 - YST 1942
307 -9:00 US Y%sT 1946
308 -9:00 - YST 1969
309 -9:00 US Y%sT 1983 Oct 30 2:00
310 -9:00 US AK%sT
311 Zone America/Anchorage 14:00:24 - LMT 1867 Oct 18
312 -9:59:36 - LMT 1900 Aug 20 12:00
313 -10:00 - CAT 1942
314 -10:00 US CAT/CAWT 1946
315 -10:00 - CAT 1967 Apr
316 -10:00 - AHST 1969
317 -10:00 US AH%sT 1983 Oct 30 2:00
318 -9:00 US AK%sT
319 Zone America/Nome 12:58:21 - LMT 1867 Oct 18
320 -11:01:38 - LMT 1900 Aug 20 12:00
321 -11:00 - NST 1942
322 -11:00 US N%sT 1946
323 -11:00 - NST 1967 Apr
324 -11:00 - BST 1969
325 -11:00 US B%sT 1983 Oct 30 2:00
326 -9:00 US AK%sT
327 Zone America/Adak 12:13:21 - LMT 1867 Oct 18
328 -11:46:38 - LMT 1900 Aug 20 12:00
329 -11:00 - NST 1942
330 -11:00 US N%sT 1946
331 -11:00 - NST 1967 Apr
332 -11:00 - BST 1969
333 -11:00 US B%sT 1983 Oct 30 2:00
334 -10:00 US HA%sT
335 # Shanks writes that part of southwest Alaska (e.g. Aniak)
336 # switched from -11:00 to -10:00 on 1968-09-22 at 02:00,
337 # and another part (e.g. Akiak) made the same switch five weeks later.
338 # These switches don't quite make our 1970 cutoff.
340 # Hawaii
341 #
342 # From Arthur David Olson:
343 # And then there's Hawaii.
344 # DST was observed for one day in 1933;
345 # standard time was changed by half an hour in 1947;
346 # it's always standard as of 1986.
347 #
348 # From Paul Eggert:
349 # Shanks says the 1933 experiment lasted for three weeks. Go with Shanks.
350 #
351 Zone Pacific/Honolulu -10:31:26 - LMT 1900 Jan 1 12:00
352 -10:30 - HST 1933 Apr 30 2:00
353 -10:30 1:00 HDT 1933 May 21 2:00
354 -10:30 US H%sT 1947 Jun 8 2:00
355 -10:00 - HST
357 # Now we turn to US areas that have diverged from the consensus since 1970.
359 # Arizona mostly uses MST.
360 Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 12:00
361 -7:00 US M%sT 1944 Jan 1 00:01
362 -7:00 - MST 1944 Mar 17 00:01
363 -7:00 US M%sT 1944 Oct 1 00:01
364 -7:00 - MST 1967
365 -7:00 US M%sT 1968
366 -7:00 - MST
367 # From Arthur David Olson (1988-02-13):
368 # A writer from the Inter Tribal Council of Arizona, Inc.,
369 # notes in private correspondence dated 12/28/87 that "Presently, only the
370 # Navajo Nation participates in the Daylight Saving Time policy, due to its
371 # large size and location in three states." (The "only" means that other
372 # tribal nations don't use DST.)
374 Link America/Denver America/Shiprock
376 # Southern Idaho and eastern Oregon switched four weeks late in 1974.
377 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
378 Zone America/Boise -7:44:49 - LMT 1883 Nov 18 12:00
379 -8:00 US P%sT 1923 May 13 2:00
380 -7:00 US M%sT 1974
381 -7:00 - MST 1974 Feb 3 2:00
382 -7:00 US M%sT
384 # Indiana
385 #
386 # For a map of Indiana's time zone regions, see:
387 # <a href="http://www.mccsc.edu/time.html">
388 # What time is it in Indiana?
389 # </a> (1999-04-06)
390 #
391 # From Paul Eggert (1995-12-19):
392 # Indiana generally observes either EST all year, or CST/CDT,
393 # but areas near Cincinnati and Louisville use those cities' timekeeping
394 # and in 1969 and 1970 the whole state observed daylight time;
395 # and there are other exceptions as noted below.
396 # Shanks partitions Indiana into 345 regions, each with its own time history,
397 # and writes ``Even newspaper reports present contradictory information.''
398 # Fortunately, most of the complexity occurred before our cutoff date of 1970.
399 #
400 # Since 1970, EST-only Indiana has been like America/Indianapolis,
401 # with exceptions noted below for Crawford, Starke, and Switzerland counties.
402 # The parts of Indiana not listed below have been like America/Chicago,
403 # America/Louisville, or America/New_York.
404 #
405 # Other than Indianapolis, the Indiana place names are so nondescript
406 # that they would be ambiguous if we left them at the `America' level.
407 # So we reluctantly put them all in a subdirectory `America/Indiana'.
408 #
409 # Most of EST-only Indiana last observed DST in 1970.
411 # From Paul Eggert (2001-03-06), following a tip by Markus Kuhn:
412 # Pam Belluck reported in the New York Times (2001-01-31) that the
413 # Indiana Legislature is considering a bill to adopt DST statewide.
414 # Her article mentioned Vevay, whose post office observes a different
415 # time zone from Danner's Hardware across the street.
417 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
418 Rule Indianapolis 1941 only - Jun 22 2:00 1:00 D
419 Rule Indianapolis 1941 1954 - Sep lastSun 2:00 0 S
420 Rule Indianapolis 1946 1954 - Apr lastSun 2:00 1:00 D
421 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
422 Zone America/Indianapolis -5:44:38 - LMT 1883 Nov 18 12:00
423 -6:00 US C%sT 1920
424 -6:00 Indianapolis C%sT 1942
425 -6:00 US C%sT 1946
426 -6:00 Indianapolis C%sT 1955 Apr 24 2:00
427 -5:00 - EST 1957 Sep 29 2:00
428 -6:00 - CST 1958 Apr 27 2:00
429 -5:00 - EST 1969
430 -5:00 US E%sT 1971
431 -5:00 - EST
432 Link America/Indianapolis America/Indiana/Indianapolis
433 #
434 # Part of Crawford County, Indiana, last observed DST in 1975,
435 # and left its clocks alone in 1974.
436 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
437 Rule Marengo 1951 only - Apr lastSun 2:00 1:00 D
438 Rule Marengo 1951 only - Sep lastSun 2:00 0 S
439 Rule Marengo 1954 1960 - Apr lastSun 2:00 1:00 D
440 Rule Marengo 1954 1960 - Sep lastSun 2:00 0 S
441 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
442 Zone America/Indiana/Marengo -5:45:23 - LMT 1883 Nov 18 12:00
443 -6:00 US C%sT 1951
444 -6:00 Marengo C%sT 1961 Apr 30 2:00
445 -5:00 - EST 1969
446 -5:00 US E%sT 1974 Jan 6 2:00
447 -6:00 1:00 CDT 1974 Oct 27 2:00
448 -5:00 US E%sT 1976
449 -5:00 - EST
450 #
451 # Starke County, Indiana
452 # From Arthur David Olson (1991-10-28):
453 # An article on page A3 of the Sunday, 1991-10-27 Washington Post
454 # notes that Starke County switched from Central time to Eastern time as of
455 # 1991-10-27.
456 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
457 Rule Starke 1947 1961 - Apr lastSun 2:00 1:00 D
458 Rule Starke 1947 1954 - Sep lastSun 2:00 0 S
459 Rule Starke 1955 1956 - Oct lastSun 2:00 0 S
460 Rule Starke 1957 1958 - Sep lastSun 2:00 0 S
461 Rule Starke 1959 1961 - Oct lastSun 2:00 0 S
462 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
463 Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 12:00
464 -6:00 US C%sT 1947
465 -6:00 Starke C%sT 1962 Apr 29 2:00
466 -5:00 - EST 1963 Oct 27 2:00
467 -6:00 US C%sT 1991 Oct 27 2:00
468 -5:00 - EST
469 #
470 # Switzerland County, Indiana, last observed DST in 1972.
471 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
472 Zone America/Indiana/Vevay -5:40:16 - LMT 1883 Nov 18 12:00
473 -6:00 US C%sT 1954 Apr 25 2:00
474 -5:00 - EST 1969
475 -5:00 US E%sT 1973
476 -5:00 - EST
478 # Part of Kentucky left its clocks alone in 1974.
479 # This also includes a part of Indiana immediately adjacent to Louisville.
480 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
481 Rule Louisville 1921 only - May 1 2:00 1:00 D
482 Rule Louisville 1921 only - Sep 1 2:00 0 S
483 Rule Louisville 1941 1961 - Apr lastSun 2:00 1:00 D
484 Rule Louisville 1941 only - Sep lastSun 2:00 0 S
485 Rule Louisville 1946 only - Jun 2 2:00 0 S
486 Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S
487 Rule Louisville 1956 1960 - Oct lastSun 2:00 0 S
488 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
489 Zone America/Louisville -5:43:02 - LMT 1883 Nov 18 12:00
490 -6:00 US C%sT 1921
491 -6:00 Louisville C%sT 1942
492 -6:00 US C%sT 1946
493 -6:00 Louisville C%sT 1961 Jul 23 2:00
494 -5:00 - EST 1968
495 -5:00 US E%sT 1974 Jan 6 2:00
496 -6:00 1:00 CDT 1974 Oct 27 2:00
497 -5:00 US E%sT
498 Link America/Louisville America/Kentucky/Louisville
499 #
500 # Wayne, Clinton, and Russell Counties, Kentucky
501 #
502 # From
503 # <a href="http://www.lake-cumberland.com/life/archive/news990129time.shtml">
504 # Lake Cumberland LIFE
505 # </a> (1999-01-29) via WKYM-101.7:
506 # Clinton County has joined Wayne County in asking the DoT to change from
507 # the Central to the Eastern time zone.... The Wayne County government made
508 # the same request in December. And while Russell County officials have not
509 # taken action, the majority of respondents to a poll conducted there in
510 # August indicated they would like to change to "fast time" also.
511 # The three Lake Cumberland counties are the farthest east of any U.S.
512 # location in the Central time zone.
513 #
514 # From Rich Wales (2000-08-29):
515 # After prolonged debate, and despite continuing deep differences of opinion,
516 # Wayne County (central Kentucky) is switching from Central (-0600) to Eastern
517 # (-0500) time. They won't "fall back" this year. See Sara Shipley,
518 # The difference an hour makes, Nando Times (2000-08-29 15:33 -0400).
519 #
520 # From Paul Eggert (2001-07-16):
521 # The final rule was published in the
522 # <a href="http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=2000_register&docid=fr17au00-22">
523 # Federal Register 65, 160 (2000-08-17), page 50154-50158.
524 # </a>
525 #
526 Zone America/Kentucky/Monticello -5:39:24 - LMT 1883 Nov 18 12:00
527 -6:00 US C%sT 1946
528 -6:00 - CST 1968
529 -6:00 US C%sT 2000 Oct 29 2:00
530 -5:00 US E%sT
533 # From Rives McDow (2000-08-30):
534 # Here ... are all the changes in the US since 1985.
535 # Kearny County, KS (put all of county on central;
536 # previously split between MST and CST) ... 1990-10
537 # Starke County, IN (from CST to EST) ... 1991-10
538 # Oliver County, ND (from MST to CST) ... 1992-10
539 # West Wendover, NV (from PST TO MST) ... 1999-10
540 # Wayne County, KY (from CST to EST) ... 2000-10
541 #
542 # From Paul Eggert (2001-07-17):
543 # We don't know where the line used to be within Kearny County, KS,
544 # so omit that change for now.
545 # See America/Indiana/Knox for the Starke County, IN change.
546 # See America/North_Dakota/Center for the Oliver County, ND change.
547 # West Wendover, NV officially switched from Pacific to mountain time on
548 # 1999-10-31. See the
549 # <a href="http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=1999_register&docid=fr21oc99-15">
550 # Federal Register 64, 203 (1999-10-21), page 56705-56707.
551 # </a>
552 # However, the Federal Register says that West Wendover already operated
553 # on mountain time, and the rule merely made this official;
554 # hence a separate tz entry is not needed.
556 # Michigan
557 #
558 # From Bob Devine (1988-01-28):
559 # Michigan didn't observe DST from 1968 to 1973.
560 #
561 # From Paul Eggert (1999-03-31):
562 # Shanks writes that Michigan started using standard time on 1885-09-18,
563 # but Howse writes (pp 124-125, referring to Popular Astronomy, 1901-01)
564 # that Detroit kept
565 #
566 # local time until 1900 when the City Council decreed that clocks should
567 # be put back twenty-eight minutes to Central Standard Time. Half the
568 # city obeyed, half refused. After considerable debate, the decision
569 # was rescinded and the city reverted to Sun time. A derisive offer to
570 # erect a sundial in front of the city hall was referred to the
571 # Committee on Sewers. Then, in 1905, Central time was adopted
572 # by city vote.
573 #
574 # This story is too entertaining to be false, so go with Howse over Shanks.
575 #
576 # From Paul Eggert (2001-03-06):
577 # Garland (1927) writes ``Cleveland and Detroit advanced their clocks
578 # one hour in 1914.'' This change is not in Shanks. We have no more
579 # info, so omit this for now.
580 #
581 # Most of Michigan observed DST from 1973 on, but was a bit late in 1975.
582 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
583 Rule Detroit 1948 only - Apr lastSun 2:00 1:00 D
584 Rule Detroit 1948 only - Sep lastSun 2:00 0 S
585 Rule Detroit 1967 only - Jun 14 2:00 1:00 D
586 Rule Detroit 1967 only - Oct lastSun 2:00 0 S
587 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
588 Zone America/Detroit -5:32:11 - LMT 1905
589 -6:00 - CST 1915 May 15 2:00
590 -5:00 - EST 1942
591 -5:00 US E%sT 1946
592 -5:00 Detroit E%sT 1973
593 -5:00 US E%sT 1975
594 -5:00 - EST 1975 Apr 27 2:00
595 -5:00 US E%sT
596 #
597 # The Michigan border with Wisconsin switched from EST to CST/CDT in 1973.
598 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
599 Rule Menominee 1946 only - Apr lastSun 2:00 1:00 D
600 Rule Menominee 1946 only - Sep lastSun 2:00 0 S
601 Rule Menominee 1966 only - Apr lastSun 2:00 1:00 D
602 Rule Menominee 1966 only - Oct lastSun 2:00 0 S
603 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
604 Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00
605 -6:00 US C%sT 1946
606 -6:00 Menominee C%sT 1969 Apr 27 2:00
607 -5:00 - EST 1973 Apr 29 2:00
608 -6:00 US C%sT
610 # Navassa
611 # administered by the US Fish and Wildlife Service
612 # claimed by US under the provisions of the 1856 Guano Islands Act
613 # also claimed by Haiti
614 # occupied 1857/1900 by the Navassa Phosphate Co
615 # US lighthouse 1917/1996-09
616 # currently uninhabited
617 # see Mark Fineman, ``An Isle Rich in Guano and Discord'',
618 # _Los Angeles Times_ (1998-11-10), A1, A10; it cites
619 # Jimmy Skaggs, _The Great Guano Rush_ (1994).
621 # Old names, for S5 users
623 # Link LINK-FROM LINK-TO
624 Link America/New_York EST5EDT
625 Link America/Chicago CST6CDT
626 Link America/Denver MST7MDT
627 Link America/Los_Angeles PST8PDT
628 Link America/Indianapolis EST
629 Link America/Phoenix MST
630 Link Pacific/Honolulu HST
632 ################################################################################
635 # From Paul Eggert <eggert@twinsun.com> (1999-10-29):
636 # A good source for time zone historical data outside the US is
637 # Thomas G. Shanks, The International Atlas (5th edition),
638 # San Diego: ACS Publications, Inc. (1999).
639 #
640 # Gwillim Law writes that a good source
641 # for recent time zone data is the International Air Transport
642 # Association's Standard Schedules Information Manual (IATA SSIM),
643 # published semiannually. Law sent in several helpful summaries
644 # of the IATA's data after 1990.
645 #
646 # Except where otherwise noted, Shanks is the source for entries through 1990,
647 # and IATA SSIM is the source for entries after 1990.
648 #
649 # Another source occasionally used is Edward W. Whitman, World Time Differences,
650 # Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated), which
651 # I found in the UCLA library.
652 #
653 # See the `europe' file for Greenland.
655 # Canada
657 # From Alain LaBont<e'> <ALB@immedia.ca> (1994-11-14):
658 # I post here the time zone abbreviations standardized in Canada
659 # for both English and French in the CAN/CSA-Z234.4-89 standard....
660 #
661 # UTC Standard time Daylight savings time
662 # offset French English French English
663 # -2:30 - - HAT NDT
664 # -3 - - HAA ADT
665 # -3:30 HNT NST - -
666 # -4 HNA AST HAE EDT
667 # -5 HNE EST HAC CDT
668 # -6 HNC CST HAR MDT
669 # -7 HNR MST HAP PDT
670 # -8 HNP PST HAY YDT
671 # -9 HNY YST - -
672 #
673 # HN: Heure Normale ST: Standard Time
674 # HA: Heure Avanc<e'>e DT: Daylight saving Time
675 #
676 # A: de l'Atlantique Atlantic
677 # C: du Centre Central
678 # E: de l'Est Eastern
679 # M: Mountain
680 # N: Newfoundland
681 # P: du Pacifique Pacific
682 # R: des Rocheuses
683 # T: de Terre-Neuve
684 # Y: du Yukon Yukon
685 #
686 # From Paul Eggert <eggert@twinsun.com> (1994-11-22):
687 # Alas, this sort of thing must be handled by localization software.
689 # Unless otherwise specified, the data for Canada are all from Shanks.
691 # From Paul Eggert (2000-10-02):
692 # H. David Matthews and Mary Vincent's map
693 # <a href="http://www.canadiangeographic.ca/SO98/geomap.htm">
694 # "It's about TIME", _Canadian Geographic_ (September-October 1998)
695 # </a> contains detailed boundaries for regions observing nonstandard
696 # time and daylight saving time arrangements in Canada circa 1998.
697 #
698 # INMS, the Institute for National Measurement Standards in Ottawa, has
699 # <a href="http://www.nrc.ca/inms/time/tze.html">
700 # information about standard and daylight saving time zones in Canada.
701 # </a> (updated periodically).
702 # Its unofficial information is often taken from Matthews and Vincent.
704 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
705 Rule Canada 1918 only - Apr 14 2:00 1:00 D
706 Rule Canada 1918 only - Oct 31 2:00 0 S
707 Rule Canada 1942 only - Feb 9 2:00 1:00 W
708 Rule Canada 1945 only - Sep 30 2:00 0 S
709 Rule Canada 1974 1986 - Apr lastSun 2:00 1:00 D
710 Rule Canada 1974 max - Oct lastSun 2:00 0 S
711 Rule Canada 1987 max - Apr Sun>=1 2:00 1:00 D
714 # Newfoundland (and far southeast Labrador)
716 # From Paul Eggert (2000-10-02):
717 # Matthews and Vincent (1998) write that Labrador should use NST/NDT,
718 # but the only part of Labrador that follows the rules is the
719 # southeast corner, including Port Hope Simpson and Mary's Harbour,
720 # but excluding, say, Black Tickle.
722 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
723 Rule StJohns 1917 1918 - Apr Sun>=8 2:00 1:00 D
724 Rule StJohns 1917 only - Sep 17 2:00 0 S
725 Rule StJohns 1918 only - Oct 31 2:00 0 S
726 # Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks.
727 Rule StJohns 1919 only - May 5 23:00 1:00 D
728 Rule StJohns 1919 only - Aug 12 23:00 0 S
729 # For 1931-1935 Whitman gives Apr same date; go with Shanks.
730 Rule StJohns 1920 1935 - May Sun>=1 23:00 1:00 D
731 Rule StJohns 1920 1935 - Oct lastSun 23:00 0 S
732 # For 1936-1941 Shanks gives May Mon>=9 and Oct Mon>=2; go with Whitman.
733 Rule StJohns 1936 1941 - May Sun>=8 0:00 1:00 D
734 Rule StJohns 1936 1941 - Oct Sun>=1 0:00 0 S
735 # Shanks gives 1942 May 11 - 1945 Sep 30; go with Whitman.
736 Rule StJohns 1942 only - Mar 1 0:00 1:00 W
737 Rule StJohns 1942 only - Dec 31 0:00 0 S
738 Rule StJohns 1943 only - May 30 0:00 1:00 W
739 Rule StJohns 1943 only - Sep 5 0:00 0 S
740 Rule StJohns 1944 only - Jul 10 0:00 1:00 W
741 Rule StJohns 1944 only - Sep 2 0:00 0 S
742 Rule StJohns 1945 only - Jan 1 0:00 1:00 W
743 Rule StJohns 1945 only - Oct 7 2:00 0 S
744 # For 1946-9 Whitman gives May 5,4,9,1 - Oct 1,5,3,2, and for 1950 he gives
745 # Apr 30 - Sep 24; go with Shanks.
746 Rule StJohns 1946 1950 - May Sun>=8 2:00 1:00 D
747 Rule StJohns 1946 1950 - Oct Sun>=2 2:00 0 S
748 Rule StJohns 1951 1986 - Apr lastSun 2:00 1:00 D
749 Rule StJohns 1951 1959 - Sep lastSun 2:00 0 S
750 Rule StJohns 1960 1986 - Oct lastSun 2:00 0 S
751 # From Paul Eggert (2000-10-02):
752 # INMS (2000-09-12) says that, since 1988 at least, Newfoundland switches
753 # at 00:01 local time. For now, assume it started in 1987.
754 Rule StJohns 1987 only - Apr Sun>=1 0:01 1:00 D
755 Rule StJohns 1987 max - Oct lastSun 0:01 0 S
756 Rule StJohns 1988 only - Apr Sun>=1 0:01 2:00 DD
757 Rule StJohns 1989 max - Apr Sun>=1 0:01 1:00 D
758 # St John's has an apostrophe, but Posix file names can't have apostrophes.
759 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
760 Zone America/St_Johns -3:30:52 - LMT 1884
761 -3:30:52 StJohns N%sT 1935 Mar 30
762 -3:30 StJohns N%sT
765 # most of east Labrador
767 # The name `Happy Valley-Goose Bay' is too long; use `Goose Bay'.
768 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
769 Zone America/Goose_Bay -4:01:40 - LMT 1884 # Happy Valley-Goose Bay
770 -3:30:52 StJohns NST 1919
771 -3:30:52 - NST 1935 Mar 30
772 -3:30 - NST 1936
773 -3:30 StJohns N%sT 1966 Mar 15 2:00
774 -4:00 StJohns A%sT
777 # west Labrador, New Brunswick, Nova Scotia, Prince Edward I
779 # From Paul Eggert (1996-06-12):
780 # Shanks writes that since 1970 most of this region has been like Halifax.
781 # Many locales did not observe peacetime DST until 1972;
782 # Glace Bay, NS is the largest that we know of.
783 # Shanks also writes that Liverpool, NS was the only town in Canada to observe
784 # DST in 1971 but not 1970; for now we'll assume this is a typo.
786 # From Paul Eggert (2000-10-02):
787 # INMS (2000-09-12) says that, since 1988 at least, New Brunswick switches
788 # at 00:01 local time. FIXME: verify and create a new Zone for this.
791 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
792 Rule Halifax 1916 only - Apr 1 0:00 1:00 D
793 Rule Halifax 1916 only - Oct 1 0:00 0 S
794 Rule Halifax 1918 only - Apr 14 2:00 1:00 D
795 Rule Halifax 1918 only - Oct 31 2:00 0 S
796 Rule Halifax 1920 only - May 9 0:00 1:00 D
797 Rule Halifax 1920 only - Aug 29 0:00 0 S
798 Rule Halifax 1921 only - May 6 0:00 1:00 D
799 Rule Halifax 1921 1922 - Sep 5 0:00 0 S
800 Rule Halifax 1922 only - Apr 30 0:00 1:00 D
801 Rule Halifax 1923 1925 - May Sun>=1 0:00 1:00 D
802 Rule Halifax 1923 only - Sep 4 0:00 0 S
803 Rule Halifax 1924 only - Sep 15 0:00 0 S
804 Rule Halifax 1925 only - Sep 28 0:00 0 S
805 Rule Halifax 1926 only - May 16 0:00 1:00 D
806 Rule Halifax 1926 only - Sep 13 0:00 0 S
807 Rule Halifax 1927 only - May 1 0:00 1:00 D
808 Rule Halifax 1927 only - Sep 26 0:00 0 S
809 Rule Halifax 1928 1931 - May Sun>=8 0:00 1:00 D
810 Rule Halifax 1928 only - Sep 9 0:00 0 S
811 Rule Halifax 1929 only - Sep 3 0:00 0 S
812 Rule Halifax 1930 only - Sep 15 0:00 0 S
813 Rule Halifax 1931 1932 - Sep Mon>=24 0:00 0 S
814 Rule Halifax 1933 only - Apr 30 0:00 1:00 D
815 Rule Halifax 1933 only - Oct 2 0:00 0 S
816 Rule Halifax 1934 only - May 20 0:00 1:00 D
817 Rule Halifax 1934 only - Sep 16 0:00 0 S
818 Rule Halifax 1935 only - Jun 2 0:00 1:00 D
819 Rule Halifax 1935 only - Sep 30 0:00 0 S
820 Rule Halifax 1936 only - Jun 1 0:00 1:00 D
821 Rule Halifax 1936 only - Sep 14 0:00 0 S
822 Rule Halifax 1937 1938 - May Sun>=1 0:00 1:00 D
823 Rule Halifax 1937 1941 - Sep Mon>=24 0:00 0 S
824 Rule Halifax 1939 only - May 28 0:00 1:00 D
825 Rule Halifax 1940 1941 - May Sun>=1 0:00 1:00 D
826 Rule Halifax 1942 only - Feb 9 2:00 1:00 W
827 Rule Halifax 1945 1959 - Sep lastSun 2:00 0 S
828 Rule Halifax 1946 1959 - Apr lastSun 2:00 1:00 D
829 Rule Halifax 1962 1986 - Apr lastSun 2:00 1:00 D
830 Rule Halifax 1962 max - Oct lastSun 2:00 0 S
831 Rule Halifax 1987 max - Apr Sun>=1 2:00 1:00 D
832 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
833 Zone America/Halifax -4:14:24 - LMT 1902 Jun 15
834 -4:00 Halifax A%sT
835 Zone America/Glace_Bay -3:59:48 - LMT 1902 Jun 15
836 -4:00 Canada A%sT 1953
837 -4:00 Halifax A%sT 1954
838 -4:00 - AST 1972
839 -4:00 Halifax A%sT
842 # Ontario, Quebec
844 # From Paul Eggert (1996-06-12):
845 # Shanks writes that since 1970 most of this region has been like Montreal.
846 # Thunder Bay skipped DST in 1973.
847 # Many smaller locales did not observe peacetime DST until 1974;
848 # Nipigon (EST) and Rainy River (CST) are the largest that we know of.
849 # Far west Ontario is like Winnipeg; far east Quebec is like Halifax.
851 # From Paul Eggert (1997-10-17):
852 # msb@sq.com writes that an article in the 1997-10-14 Toronto Star
853 # says that Atikokan, Ontario currently does not observe DST,
854 # but will vote on 11-10 whether to use EST/EDT.
855 # He also writes that the
856 # <a href="http://www.gov.on.ca/MBS/english/publications/statregs/conttext.html">
857 # Ontario Time Act (1990, Chapter T.9)
858 # </a>
859 # says that Ontario east of 90W uses EST/EDT, and west of 90W uses CST/CDT.
860 # Officially Atikokan is therefore on CST/CDT, and most likely this report
861 # concerns a non-official time observed as a matter of local practice.
862 # For what it's worth, Shanks says that Atikokan has agreed with
863 # Rainy River ever since standard time was introduced.
865 # From Paul Eggert (2000-10-02):
866 # Matthews and Vincent (1998) write that Atikokan, Pickle Lake, and
867 # New Osnaburgh observe CST all year, that Big Trout Lake observes
868 # CST/CDT, and that Upsala and Shebandowan observe EST/EDT, all in
869 # violation of the official Ontario rules.
870 # They also write that Quebec east of the -63 meridian is supposed to
871 # observe AST, but residents as far east as Natashquan use EST/EDT,
872 # and residents east of Natashquan use AST.
873 # We probably need Zones for far east Quebec and for Atikokan,
874 # but we don't know when their practices started.
876 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
877 Rule Mont 1917 only - Mar 25 2:00 1:00 D
878 Rule Mont 1917 only - Apr 24 0:00 0 S
879 Rule Mont 1918 only - Apr 14 2:00 1:00 D
880 Rule Mont 1918 only - Oct 31 2:00 0 S
881 Rule Mont 1919 only - Mar 31 2:30 1:00 D
882 Rule Mont 1919 only - Oct 25 2:30 0 S
883 Rule Mont 1920 only - May 2 2:30 1:00 D
884 Rule Mont 1920 only - Oct 3 2:30 0 S
885 Rule Mont 1921 only - May 1 2:00 1:00 D
886 Rule Mont 1921 only - Oct 2 2:30 0 S
887 Rule Mont 1922 only - Apr 30 2:00 1:00 D
888 Rule Mont 1922 only - Oct 1 2:30 0 S
889 Rule Mont 1924 only - May 17 2:00 1:00 D
890 Rule Mont 1924 1926 - Sep lastSun 2:30 0 S
891 Rule Mont 1925 1926 - May Sun>=1 2:00 1:00 D
892 Rule Mont 1927 only - May 1 0:00 1:00 D
893 Rule Mont 1927 1932 - Sep Sun>=25 0:00 0 S
894 Rule Mont 1928 1931 - Apr Sun>=25 0:00 1:00 D
895 Rule Mont 1932 only - May 1 0:00 1:00 D
896 Rule Mont 1933 1940 - Apr Sun>=24 0:00 1:00 D
897 Rule Mont 1933 only - Oct 1 0:00 0 S
898 Rule Mont 1934 1939 - Sep Sun>=24 0:00 0 S
899 Rule Mont 1945 1948 - Sep lastSun 2:00 0 S
900 Rule Mont 1946 1986 - Apr lastSun 2:00 1:00 D
901 Rule Mont 1949 1950 - Oct lastSun 2:00 0 S
902 Rule Mont 1951 1956 - Sep lastSun 2:00 0 S
903 Rule Mont 1957 max - Oct lastSun 2:00 0 S
904 Rule Mont 1987 max - Apr Sun>=1 2:00 1:00 D
905 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
906 Zone America/Montreal -4:54:16 - LMT 1884
907 -5:00 Mont E%sT
908 Zone America/Thunder_Bay -5:57:00 - LMT 1895
909 -5:00 Canada E%sT 1970
910 -5:00 Mont E%sT 1973
911 -5:00 - EST 1974
912 -5:00 Canada E%sT
913 Zone America/Nipigon -5:53:04 - LMT 1895
914 -5:00 Canada E%sT
915 Zone America/Rainy_River -6:17:56 - LMT 1895
916 -6:00 Canada C%sT
919 # Manitoba
921 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
922 Rule Winn 1916 only - Apr 23 0:00 1:00 D
923 Rule Winn 1916 only - Sep 17 0:00 0 S
924 Rule Winn 1918 only - Apr 14 2:00 1:00 D
925 Rule Winn 1918 only - Oct 31 2:00 0 S
926 Rule Winn 1937 only - May 16 2:00 1:00 D
927 Rule Winn 1937 only - Sep 26 2:00 0 S
928 Rule Winn 1942 only - Feb 9 2:00 1:00 W
929 Rule Winn 1945 only - Sep lastSun 2:00 0 S
930 Rule Winn 1946 only - May 12 2:00 1:00 D
931 Rule Winn 1946 only - Oct 13 2:00 0 S
932 Rule Winn 1947 1949 - Apr lastSun 2:00 1:00 D
933 Rule Winn 1947 1949 - Sep lastSun 2:00 0 S
934 Rule Winn 1950 only - May 1 2:00 1:00 D
935 Rule Winn 1950 only - Sep 30 2:00 0 S
936 Rule Winn 1951 1960 - Apr lastSun 2:00 1:00 D
937 Rule Winn 1951 1958 - Sep lastSun 2:00 0 S
938 Rule Winn 1959 only - Oct lastSun 2:00 0 S
939 Rule Winn 1960 only - Sep lastSun 2:00 0 S
940 Rule Winn 1963 only - Apr lastSun 2:00 1:00 D
941 Rule Winn 1963 only - Sep 22 2:00 0 S
942 Rule Winn 1966 1986 - Apr lastSun 2:00 1:00 D
943 Rule Winn 1966 1986 - Oct lastSun 2:00 0 S
944 Rule Winn 1987 max - Apr Sun>=1 2:00 1:00 D
945 # From Paul Eggert (2000-10-02):
946 # INMS (2000-09-12) says that, since 1988 at least, Manitoba switches from
947 # DST at 03:00 local time. For now, assume it started in 1987.
948 Rule Winn 1987 max - Oct lastSun 2:00s 0 S
949 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
950 Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16
951 -6:00 Winn C%sT
954 # Saskatchewan
956 # From Paul Eggert (2000-10-02):
957 # Shanks writes that since 1970 most of this region has been like Regina.
958 # Some western towns (e.g. Swift Current) switched from MST/MDT to CST in 1972.
959 # Other western towns (e.g. Lloydminster) are like Edmonton.
960 # Matthews and Vincent (1998) write that Denare Beach and Creighton
961 # are like Winnipeg, in violation of Saskatchewan law.
963 # From W. Jones <jones@skdad.usask.ca> (1992-11-06):
964 # The. . .below is based on information I got from our law library, the
965 # provincial archives, and the provincial Community Services department.
966 # A precise history would require digging through newspaper archives, and
967 # since you didn't say what you wanted, I didn't bother.
968 #
969 # Saskatchewan is split by a time zone meridian (105W) and over the years
970 # the boundary became pretty ragged as communities near it reevaluated
971 # their affiliations in one direction or the other. In 1965 a provincial
972 # referendum favoured legislating common time practices.
973 #
974 # On 15 April 1966 the Time Act (c. T-14, Revised Statutes of
975 # Saskatchewan 1978) was proclaimed, and established that the eastern
976 # part of Saskatchewan would use CST year round, that districts in
977 # northwest Saskatchewan would by default follow CST but could opt to
978 # follow Mountain Time rules (thus 1 hour difference in the winter and
979 # zero in the summer), and that districts in southwest Saskatchewan would
980 # by default follow MT but could opt to follow CST.
981 #
982 # It took a few years for the dust to settle (I know one story of a town
983 # on one time zone having its school in another, such that a mom had to
984 # serve her family lunch in two shifts), but presently it seems that only
985 # a few towns on the border with Alberta (e.g. Lloydminster) follow MT
986 # rules any more; all other districts appear to have used CST year round
987 # since sometime in the 1960s.
989 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
990 Rule Regina 1918 only - Apr 14 2:00 1:00 D
991 Rule Regina 1918 only - Oct 31 2:00 0 S
992 Rule Regina 1930 1934 - May Sun>=1 0:00 1:00 D
993 Rule Regina 1930 1934 - Oct Sun>=1 0:00 0 S
994 Rule Regina 1937 1941 - Apr Sun>=8 0:00 1:00 D
995 Rule Regina 1937 only - Oct Sun>=8 0:00 0 S
996 Rule Regina 1938 only - Oct Sun>=1 0:00 0 S
997 Rule Regina 1939 1941 - Oct Sun>=8 0:00 0 S
998 Rule Regina 1942 only - Feb 9 2:00 1:00 W
999 Rule Regina 1945 only - Sep lastSun 2:00 0 S
1000 Rule Regina 1946 only - Apr Sun>=8 2:00 1:00 D
1001 Rule Regina 1946 only - Oct Sun>=8 2:00 0 S
1002 Rule Regina 1947 1959 - Apr lastSun 2:00 1:00 D
1003 Rule Regina 1947 1958 - Sep lastSun 2:00 0 S
1004 Rule Regina 1959 only - Oct lastSun 2:00 0 S
1005 #
1006 Rule Swift 1957 only - Apr lastSun 2:00 1:00 D
1007 Rule Swift 1957 only - Oct lastSun 2:00 0 S
1008 Rule Swift 1959 1961 - Apr lastSun 2:00 1:00 D
1009 Rule Swift 1959 only - Oct lastSun 2:00 0 S
1010 Rule Swift 1960 1961 - Sep lastSun 2:00 0 S
1011 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1012 Zone America/Regina -6:58:36 - LMT 1905 Sep
1013 -7:00 Regina M%sT 1960 Apr lastSun 2:00
1014 -6:00 - CST
1015 Zone America/Swift_Current -7:11:20 - LMT 1905 Sep
1016 -7:00 Canada M%sT 1946 Apr lastSun 2:00
1017 -7:00 Regina M%sT 1950
1018 -7:00 Swift M%sT 1972 Apr lastSun 2:00
1019 -6:00 - CST
1022 # Alberta
1024 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1025 Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D
1026 Rule Edm 1918 only - Oct 31 2:00 0 S
1027 Rule Edm 1919 only - May 27 2:00 0 S
1028 Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D
1029 Rule Edm 1920 only - Oct lastSun 2:00 0 S
1030 Rule Edm 1921 1923 - Sep lastSun 2:00 0 S
1031 Rule Edm 1942 only - Feb 9 2:00 1:00 W
1032 Rule Edm 1945 only - Sep lastSun 2:00 0 S
1033 Rule Edm 1947 only - Apr lastSun 2:00 1:00 D
1034 Rule Edm 1947 only - Sep lastSun 2:00 0 S
1035 Rule Edm 1967 only - Apr lastSun 2:00 1:00 D
1036 Rule Edm 1967 only - Oct lastSun 2:00 0 S
1037 Rule Edm 1969 only - Apr lastSun 2:00 1:00 D
1038 Rule Edm 1969 only - Oct lastSun 2:00 0 S
1039 Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D
1040 Rule Edm 1972 max - Oct lastSun 2:00 0 S
1041 Rule Edm 1987 max - Apr Sun>=1 2:00 1:00 D
1042 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1043 Zone America/Edmonton -7:33:52 - LMT 1906 Sep
1044 -7:00 Edm M%sT
1047 # British Columbia
1049 # From Paul Eggert (2000-10-02):
1050 # Shanks writes that since 1970 most of this region has been like Vancouver.
1051 # Dawson Creek uses MST. Much of east BC is like Edmonton.
1052 # Matthews and Vincent (1998) write that Creston is like Dawson Creek.
1054 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1055 Rule Vanc 1918 only - Apr 14 2:00 1:00 D
1056 Rule Vanc 1918 only - Oct 31 2:00 0 S
1057 Rule Vanc 1942 only - Feb 9 2:00 1:00 W
1058 Rule Vanc 1945 only - Sep 30 2:00 0 S
1059 Rule Vanc 1946 1986 - Apr lastSun 2:00 1:00 D
1060 Rule Vanc 1946 only - Oct 13 2:00 0 S
1061 Rule Vanc 1947 1961 - Sep lastSun 2:00 0 S
1062 Rule Vanc 1962 max - Oct lastSun 2:00 0 S
1063 Rule Vanc 1987 max - Apr Sun>=1 2:00 1:00 D
1064 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1065 Zone America/Vancouver -8:12:28 - LMT 1884
1066 -8:00 Vanc P%sT
1067 Zone America/Dawson_Creek -8:00:56 - LMT 1884
1068 -8:00 Canada P%sT 1947
1069 -8:00 Vanc P%sT 1972 Aug 30 2:00
1070 -7:00 - MST
1073 # Northwest Territories, Nunavut, Yukon
1075 # From Paul Eggert (1999-10-29):
1076 # Dawson switched to PST in 1973. Inuvik switched to MST in 1979.
1077 # Mathew Englander <mathew@io.org> (1996-10-07) gives the following refs:
1078 # * 1967. Paragraph 28(34)(g) of the Interpretation Act, S.C. 1967-68,
1079 # c. 7 defines Yukon standard time as UTC-9. This is still valid;
1080 # see Interpretation Act, R.S.C. 1985, c. I-21, s. 35(1).
1081 # * C.O. 1973/214 switched Yukon to PST on 1973-10-28 00:00.
1082 # * O.I.C. 1980/02 established DST.
1083 # * O.I.C. 1987/056 changed DST to Apr firstSun 2:00 to Oct lastSun 2:00.
1084 # Shanks says Yukon's 1973-10-28 switch was at 2:00; go with Englander.
1086 # From Rives McDow (1999-09-04):
1087 # Nunavut ... moved ... to incorporate the whole territory into one time zone.
1088 # <a href="http://www.nunatsiaq.com/nunavut/nvt90903_13.html">
1089 # Nunavut moves to single time zone Oct. 31
1090 # </a>
1091 #
1092 # From Antoine Leca (1999-09-06):
1093 # We then need to create a new timezone for the Kitikmeot region of Nunavut
1094 # to differentiate it from the Yellowknife region.
1096 # From Paul Eggert (1999-09-20):
1097 # <a href="http://www.nunavut.com/basicfacts/english/basicfacts_1territory.html">
1098 # Basic Facts: The New Territory
1099 # </a> (1999) reports that Pangnirtung operates on eastern time,
1100 # and that Coral Harbour does not observe DST. We don't know when
1101 # Pangnirtung switched to eastern time; we'll guess 1995.
1102 # We'll ignore the claim about Coral Harbour for now,
1103 # since we have no further info.
1105 # From Rives McDow (1999-11-08):
1106 # On October 31, when the rest of Nunavut went to Central time,
1107 # Pangnirtung wobbled. Here is the result of their wobble:
1108 #
1109 # The following businesses and organizations in Pangnirtung use Central Time:
1110 #
1111 # First Air, Power Corp, Nunavut Construction, Health Center, RCMP,
1112 # Eastern Arctic National Parks, A & D Specialist
1113 #
1114 # The following businesses and organizations in Pangnirtung use Eastern Time:
1115 #
1116 # Hamlet office, All other businesses, Both schools, Airport operator
1117 #
1118 # This has made for an interesting situation there, which warranted the news.
1119 # No one there that I spoke with seems concerned, or has plans to
1120 # change the local methods of keeping time, as it evidently does not
1121 # really interfere with any activities or make things difficult locally.
1122 # They plan to celebrate New Year's turn-over twice, one hour apart,
1123 # so it appears that the situation will last at least that long.
1124 # The Nunavut Intergovernmental Affairs hopes that they will "come to
1125 # their senses", but the locals evidently don't see any problem with
1126 # the current state of affairs.
1128 # From Michaela Rodrigue, writing in the
1129 # <a href="http://www.nunatsiaq.com/archives/nunavut991130/nvt91119_17.html">
1130 # Nunatsiaq News (1999-11-19)</a>:
1131 # Clyde River, Pangnirtung and Sanikiluaq now operate with two time zones,
1132 # central - or Nunavut time - for government offices, and eastern time
1133 # for municipal offices and schools.... Igloolik [was similar but then]
1134 # made the switch to central time on Saturday, Nov. 6.
1136 # From Paul Eggert (2000-10-02):
1137 # Matthews and Vincent (1998) say the following, but we lack histories
1138 # for these potential new Zones.
1139 #
1140 # The Canadian Forces station at Alert uses Eastern Time while the
1141 # handful of residents at the Eureka weather station [in the Central
1142 # zone] skip daylight savings. Baffin Island, which is crossed by the
1143 # Central, Eastern and Atlantic Time zones only uses Eastern Time.
1144 # Gjoa Haven, Taloyoak and Pelly Bay all use Mountain instead of
1145 # Central Time and Southampton Island [in the Central zone] is not
1146 # required to use daylight savings.
1148 # From
1149 # <a href="http://www.nunatsiaq.com/archives/nunavut001130/nvt21110_02.html">
1150 # Nunavut now has two time zones
1151 # </a> (2000-11-10):
1152 # The Nunavut government would allow its employees in Kugluktuk and
1153 # Cambridge Bay to operate on central time year-round, putting them
1154 # one hour behind the rest of Nunavut for six months during the winter.
1155 # At the end of October the two communities had rebelled against
1156 # Nunavut's unified time zone, refusing to shift to eastern time with
1157 # the rest of the territory for the winter. Cambridge Bay remained on
1158 # central time, while Kugluktuk, even farther west, reverted to
1159 # mountain time, which they had used before the advent of Nunavut's
1160 # unified time zone in 1999.
1161 #
1162 # From Rives McDow (2001-01-20), quoting the Nunavut government:
1163 # The preceding decision came into effect at midnight, Saturday Nov 4, 2000.
1165 # From Paul Eggert (2000-12-04):
1166 # Let's just keep track of the official times for now.
1168 # From Rives McDow (2001-03-07):
1169 # The premier of Nunavut has issued a ministerial statement advising
1170 # that effective 2001-04-01, the territory of Nunavut will revert
1171 # back to three time zones (mountain, central, and eastern). Of the
1172 # cities in Nunavut, Coral Harbor is the only one that I know of that
1173 # has said it will not observe dst, staying on EST year round. I'm
1174 # checking for more info, and will get back to you if I come up with
1175 # more.
1176 # [Also see <http://www.nunatsiaq.com/nunavut/nvt10309_06.html> (2001-03-09).]
1178 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1179 Rule NT_YK 1918 only - Apr 14 2:00 1:00 D
1180 Rule NT_YK 1918 only - Oct 27 2:00 0 S
1181 Rule NT_YK 1919 only - May 25 2:00 1:00 D
1182 Rule NT_YK 1919 only - Nov 1 0:00 0 S
1183 Rule NT_YK 1942 only - Feb 9 2:00 1:00 W
1184 Rule NT_YK 1945 only - Sep 30 2:00 0 S
1185 Rule NT_YK 1965 only - Apr lastSun 0:00 2:00 DD
1186 Rule NT_YK 1965 only - Oct lastSun 2:00 0 S
1187 Rule NT_YK 1980 1986 - Apr lastSun 2:00 1:00 D
1188 Rule NT_YK 1980 max - Oct lastSun 2:00 0 S
1189 Rule NT_YK 1987 max - Apr Sun>=1 2:00 1:00 D
1190 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1191 Zone America/Pangnirtung -4:22:56 - LMT 1884
1192 -4:00 NT_YK A%sT 1995 Apr Sun>=1 2:00
1193 -5:00 Canada E%sT 1999 Oct 31 2:00
1194 -6:00 Canada C%sT 2000 Oct 29 2:00
1195 -5:00 Canada E%sT
1196 Zone America/Iqaluit -4:33:52 - LMT 1884 # Frobisher Bay before 1987
1197 -5:00 NT_YK E%sT 1999 Oct 31 2:00
1198 -6:00 Canada C%sT 2000 Oct 29 2:00
1199 -5:00 Canada E%sT
1200 Zone America/Rankin_Inlet -6:08:40 - LMT 1884
1201 -6:00 NT_YK C%sT 2000 Oct 29 2:00
1202 -5:00 - EST 2001 Apr 1 3:00
1203 -6:00 Canada C%sT
1204 Zone America/Cambridge_Bay -7:00:20 - LMT 1884
1205 -7:00 NT_YK M%sT 1999 Oct 31 2:00
1206 -6:00 Canada C%sT 2000 Oct 29 2:00
1207 -5:00 - EST 2000 Nov 5 0:00
1208 -6:00 - CST 2001 Apr 1 3:00
1209 -7:00 Canada M%sT
1210 Zone America/Yellowknife -7:37:24 - LMT 1884
1211 -7:00 NT_YK M%sT
1212 Zone America/Inuvik -8:54:00 - LMT 1884
1213 -8:00 NT_YK P%sT 1979 Apr lastSun 2:00
1214 -7:00 NT_YK M%sT
1215 Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20
1216 -9:00 NT_YK Y%sT 1966 Jul 1 2:00
1217 -8:00 NT_YK P%sT
1218 Zone America/Dawson -9:17:40 - LMT 1900 Aug 20
1219 -9:00 NT_YK Y%sT 1973 Oct 28 0:00
1220 -8:00 NT_YK P%sT
1223 ###############################################################################
1225 # Mexico
1227 # From Paul Eggert (2001-03-05):
1228 # The Investigation and Analysis Service of the
1229 # Mexican Library of Congress (MLoC) has published a
1230 # <a href="http://www.cddhcu.gob.mx/bibliot/publica/inveyana/polisoc/horver/">
1231 # history of Mexican local time (in Spanish)
1232 # </a>.
1233 #
1234 # Here are the discrepancies between Shanks and the MLoC.
1235 # (In all cases we go with the MLoC.)
1236 # Shanks reports that Baja was at -8:00 in 1922/1923.
1237 # Shanks says the 1930 transition in Baja was 1930-11-16.
1238 # Shanks reports no DST during summer 1931.
1239 # Shanks reports a transition at 1032-03-30 23:00, not 1932-04-01.
1240 # Shanks does not report transitions for Baja in 1945 or 1948.
1241 # Shanks reports southern Mexico transitions on 1981-12-01, not 12-23.
1242 # Shanks says Quintana Roo switched to -6:00 on 1982-12-02, and to -5:00
1243 # on 1997-10-26 at 02:00.
1245 # From Gwillim Law (2001-02-20):
1246 # There are some other discrepancies between the Decrees page and the
1247 # tz database. I think they can best be explained by supposing that
1248 # the researchers who prepared the Decrees page failed to find some of
1249 # the relevant documents.
1251 # From Paul Eggert (2000-07-26):
1252 # Shanks gives 1942-04-01 instead of 1942-04-24, and omits the 1981
1253 # and 1988 DST experiments. Go with spin.com.mx.
1255 # From Alan Perry <alan.perry@eng.sun.com> (1996-02-15):
1256 # A guy from our Mexico subsidiary finally found the Presidential Decree
1257 # outlining the timezone changes in Mexico.
1258 #
1259 # ------------- Begin Forwarded Message -------------
1260 #
1261 # I finally got my hands on the Official Presidential Decree that sets up the
1262 # rules for the DST changes. The rules are:
1263 #
1264 # 1. The country is divided in 3 timezones:
1265 # - Baja California Norte (the Mexico/BajaNorte TZ)
1266 # - Baja California Sur, Nayarit, Sinaloa and Sonora (the Mexico/BajaSur TZ)
1267 # - The rest of the country (the Mexico/General TZ)
1268 #
1269 # 2. From the first Sunday in April at 2:00 AM to the last Sunday in October
1270 # at 2:00 AM, the times in each zone are as follows:
1271 # BajaNorte: GMT+7
1272 # BajaSur: GMT+6
1273 # General: GMT+5
1274 #
1275 # 3. The rest of the year, the times are as follows:
1276 # BajaNorte: GMT+8
1277 # BajaSur: GMT+7
1278 # General: GMT+6
1279 #
1280 # The Decree was published in Mexico's Official Newspaper on January 4th.
1281 #
1282 # -------------- End Forwarded Message --------------
1283 # From Paul Eggert (1996-06-12):
1284 # For an English translation of the decree, see
1285 # <a href="http://mexico-travel.com/extra/timezone_eng.html">
1286 # ``Diario Oficial: Time Zone Changeover'' (1996-01-04).
1287 # </a>
1289 # From Rives McDow (1998-10-08):
1290 # The State of Quintana Roo has reverted back to central STD and DST times
1291 # (i.e. UTC -0600 and -0500 as of 1998-08-02).
1293 # From Rives McDow (2000-01-10):
1294 # Effective April 4, 1999 at 2:00 AM local time, Sonora changed to the time
1295 # zone 5 hours from the International Date Line, and will not observe daylight
1296 # savings time so as to stay on the same time zone as the southern part of
1297 # Arizona year round.
1299 # From Jesper Norgaard, translating
1300 # <http://www.reforma.com/nacional/articulo/064327/> (2001-01-17):
1301 # In Oaxaca, the 55.000 teachers from the Section 22 of the National
1302 # Syndicate of Education Workers, refuse to apply daylight saving each
1303 # year, so that the more than 10,000 schools work at normal hour the
1304 # whole year.
1306 # From Gwillim Law (2001-01-19):
1307 # <http://www.reforma.com/negocios_y_dinero/articulo/064481/> ... says
1308 # (translated):...
1309 # January 17, 2000 - The Energy Secretary, Ernesto Martens, announced
1310 # that Summer Time will be reduced from seven to five months, starting
1311 # this year....
1312 # <http://www.publico.com.mx/scripts/texto3.asp?action=pagina&pag=21&pos=p&secc=naci&date=01/17/2001>
1313 # [translated], says "summer time will ... take effect on the first Sunday
1314 # in May, and end on the last Sunday of September.
1316 # From Arthur David Olson (2001-01-25):
1317 # The 2001-01-24 traditional Washington Post contained the page one
1318 # story "Timely Issue Divides Mexicans."...
1319 # http://www.washingtonpost.com/wp-dyn/articles/A37383-2001Jan23.html
1320 # ... Mexico City Mayor Lopez Obrador "...is threatening to keep
1321 # Mexico City and its 20 million residents on a different time than
1322 # the rest of the country..." In particular, Lopez Obrador would abolish
1323 # observation of Daylight Saving Time.
1325 # <a href="http://www.conae.gob.mx/ahorro/decretohorver2001.html#decre">
1326 # Official statute published by the Energy Department
1327 # </a> (2001-02-01) shows Baja and Chihauhua as still using US DST rules,
1328 # and Sonora with no DST. This was reported by Jesper Norgaard (2001-02-03).
1330 # From Paul Eggert (2001-03-03):
1331 #
1332 # <a href="http://www.latimes.com/news/nation/20010303/t000018766.html">
1333 # James F. Smith writes in today's LA Times
1334 # </a>
1335 # * Sonora will continue to observe standard time.
1336 # * Last week Mexico City's mayor Andres Manuel Lopez Obrador decreed that
1337 # the Federal District will not adopt DST.
1338 # * 4 of 16 district leaders announced they'll ignore the decree.
1339 # * The decree does not affect federal-controlled facilities including
1340 # the airport, banks, hospitals, and schools.
1341 #
1342 # For now we'll assume that the Federal District will bow to federal rules.
1344 # From Jesper Norgaard (2001-04-01):
1345 # I found some references to the Mexican application of daylight
1346 # saving, which modifies what I had already sent you, stating earlier
1347 # that a number of northern Mexican states would go on daylight
1348 # saving. The modification reverts this to only cover Baja California
1349 # (Norte), while all other states (except Sonora, who has no daylight
1350 # saving all year) will follow the original decree of president
1351 # Vicente Fox, starting daylight saving May 6, 2001 and ending
1352 # September 30, 2001.
1353 # References: "Diario de Monterrey" <www.diariodemonterrey.com/index.asp>
1354 # Palabra <http://palabra.infosel.com/010331/primera/ppri3101.pdf> (2001-03-31)
1356 # From Reuters (2001-09-04):
1357 # Mexico's Supreme Court on Tuesday declared that daylight savings was
1358 # unconstitutional in Mexico City, creating the possibility the
1359 # capital will be in a different time zone from the rest of the nation
1360 # next year.... The Supreme Court's ruling takes effect at 2:00
1361 # a.m. (0800 GMT) on Sept. 30, when Mexico is scheduled to revert to
1362 # standard time. "This is so residents of the Federal District are not
1363 # subject to unexpected time changes," a statement from the court said.
1365 # From Jesper Norgaard Welen (2002-03-12):
1366 # ... consulting my local grocery store(!) and my coworkers, they all insisted
1367 # that a new decision had been made to reinstate US style DST in Mexico....
1368 # http://www.conae.gob.mx/ahorro/horaver2001_m1_2002.html (2002-02-20)
1369 # confirms this. Sonora as usual is the only state where DST is not applied.
1371 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1372 Rule Mexico 1939 only - Feb 5 0:00 1:00 D
1373 Rule Mexico 1939 only - Jun 25 0:00 0 S
1374 Rule Mexico 1940 only - Dec 9 0:00 1:00 D
1375 Rule Mexico 1941 only - Apr 1 0:00 0 S
1376 Rule Mexico 1943 only - Dec 16 0:00 1:00 W
1377 Rule Mexico 1944 only - May 1 0:00 0 S
1378 Rule Mexico 1950 only - Feb 12 0:00 1:00 D
1379 Rule Mexico 1950 only - Jul 30 0:00 0 S
1380 Rule Mexico 1996 2000 - Apr Sun>=1 2:00 1:00 D
1381 Rule Mexico 1996 2000 - Oct lastSun 2:00 0 S
1382 Rule Mexico 2001 only - May Sun>=1 2:00 1:00 D
1383 Rule Mexico 2001 only - Sep lastSun 2:00 0 S
1384 Rule Mexico 2002 max - Apr Sun>=1 2:00 1:00 D
1385 Rule Mexico 2002 max - Oct lastSun 2:00 0 S
1386 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1387 # Quintana Roo
1388 Zone America/Cancun -5:47:04 - LMT 1922 Jan 1 0:12:56
1389 -6:00 - CST 1981 Dec 23
1390 -5:00 Mexico E%sT 1998 Aug 2 2:00
1391 -6:00 Mexico C%sT
1392 # Campeche, Yucatan
1393 Zone America/Merida -5:58:28 - LMT 1922 Jan 1 0:01:32
1394 -6:00 - CST 1981 Dec 23
1395 -5:00 - EST 1982 Dec 2
1396 -6:00 Mexico C%sT
1397 # Coahuila, Durango, Nuevo Leon, Tamaulipas
1398 Zone America/Monterrey -6:41:16 - LMT 1921 Dec 31 23:18:44
1399 -6:00 - CST 1988
1400 -6:00 US C%sT 1989
1401 -6:00 Mexico C%sT
1402 # Central Mexico
1403 Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 0:23:24
1404 -7:00 - MST 1927 Jun 10 23:00
1405 -6:00 - CST 1930 Nov 15
1406 -7:00 - MST 1931 May 1 23:00
1407 -6:00 - CST 1931 Oct
1408 -7:00 - MST 1932 Apr 1
1409 -6:00 Mexico C%sT 2001 Sep 30 02:00
1410 -6:00 - CST 2002 Feb 20
1411 -6:00 Mexico C%sT
1412 # Chihuahua
1413 Zone America/Chihuahua -7:04:20 - LMT 1921 Dec 31 23:55:40
1414 -7:00 - MST 1927 Jun 10 23:00
1415 -6:00 - CST 1930 Nov 15
1416 -7:00 - MST 1931 May 1 23:00
1417 -6:00 - CST 1931 Oct
1418 -7:00 - MST 1932 Apr 1
1419 -6:00 - CST 1996
1420 -6:00 Mexico C%sT 1998
1421 -6:00 - CST 1998 Apr Sun>=1 3:00
1422 -7:00 Mexico M%sT
1423 # Sonora
1424 Zone America/Hermosillo -7:23:52 - LMT 1921 Dec 31 23:36:08
1425 -7:00 - MST 1927 Jun 10 23:00
1426 -6:00 - CST 1930 Nov 15
1427 -7:00 - MST 1931 May 1 23:00
1428 -6:00 - CST 1931 Oct
1429 -7:00 - MST 1932 Apr 1
1430 -6:00 - CST 1942 Apr 24
1431 -7:00 - MST 1949 Jan 14
1432 -8:00 - PST 1970
1433 -7:00 Mexico M%sT 1999
1434 -7:00 - MST
1435 # Baja California Sur, Nayarit, Sinaloa
1436 Zone America/Mazatlan -7:05:40 - LMT 1921 Dec 31 23:54:20
1437 -7:00 - MST 1927 Jun 10 23:00
1438 -6:00 - CST 1930 Nov 15
1439 -7:00 - MST 1931 May 1 23:00
1440 -6:00 - CST 1931 Oct
1441 -7:00 - MST 1932 Apr 1
1442 -6:00 - CST 1942 Apr 24
1443 -7:00 - MST 1949 Jan 14
1444 -8:00 - PST 1970
1445 -7:00 Mexico M%sT
1446 # Baja California
1447 Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 0:11:56
1448 -7:00 - MST 1924
1449 -8:00 - PST 1927 Jun 10 23:00
1450 -7:00 - MST 1930 Nov 15
1451 -8:00 - PST 1931 Apr 1
1452 -8:00 1:00 PDT 1931 Sep 30
1453 -8:00 - PST 1942 Apr 24
1454 -8:00 1:00 PWT 1945 Nov 12
1455 -8:00 - PST 1948 Apr 5
1456 -8:00 1:00 PDT 1949 Jan 14
1457 -8:00 - PST 1954
1458 -8:00 CA P%sT 1961
1459 -8:00 - PST 1976
1460 -8:00 US P%sT 1996
1461 -8:00 Mexico P%sT 2001
1462 -8:00 US P%sT 2002 Feb 20
1463 -8:00 Mexico P%sT
1464 # From Paul Eggert (2001-03-05):
1465 # Formerly there was an America/Ensenada zone, which differed from
1466 # America/Tijuana only in that it did not observe DST from 1976
1467 # through 1995. This was as per Shanks. However, Guy Harris reports
1468 # that the 1987 OAG says "Only Ensenada, Mexicale, San Felipe and
1469 # Tijuana observe DST," which contradicts Shanks but does imply that
1470 # DST-observance was a town-by-town matter back then. This concerns
1471 # data after 1970 so most likely there should be at least one Zone
1472 # other than America/Tijuana for Baja, but it's not clear yet what its
1473 # name or contents should be.
1474 #
1475 # Revillagigedo Is
1476 # no information
1478 ###############################################################################
1480 # Anguilla
1481 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1482 Zone America/Anguilla -4:12:16 - LMT 1912 Mar 2
1483 -4:00 - AST
1485 # Antigua and Barbuda
1486 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1487 Zone America/Antigua -4:07:12 - LMT 1912 Mar 2
1488 -5:00 - EST 1951
1489 -4:00 - AST
1491 # Bahamas
1492 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1493 Rule Bahamas 1964 max - Oct lastSun 2:00 0 S
1494 Rule Bahamas 1964 1986 - Apr lastSun 2:00 1:00 D
1495 Rule Bahamas 1987 max - Apr Sun>=1 2:00 1:00 D
1496 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1497 Zone America/Nassau -5:09:24 - LMT 1912 Mar 2
1498 -5:00 Bahamas E%sT
1500 # Barbados
1501 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1502 Rule Barb 1977 only - Jun 12 2:00 1:00 D
1503 Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S
1504 Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D
1505 Rule Barb 1979 only - Sep 30 2:00 0 S
1506 Rule Barb 1980 only - Sep 25 2:00 0 S
1507 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1508 Zone America/Barbados -3:58:28 - LMT 1924 # Bridgetown
1509 -3:58:28 - BMT 1932 # Bridgetown Mean Time
1510 -4:00 Barb A%sT
1512 # Belize
1513 # Whitman entirely disagrees with Shanks; go with Shanks.
1514 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1515 Rule Belize 1918 1942 - Oct Sun>=2 0:00 0:30 HD
1516 Rule Belize 1919 1943 - Feb Sun>=9 0:00 0 S
1517 Rule Belize 1973 only - Dec 5 0:00 1:00 D
1518 Rule Belize 1974 only - Feb 9 0:00 0 S
1519 Rule Belize 1982 only - Dec 18 0:00 1:00 D
1520 Rule Belize 1983 only - Feb 12 0:00 0 S
1521 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1522 Zone America/Belize -5:52:48 - LMT 1912 Apr
1523 -6:00 Belize C%sT
1525 # Bermuda
1526 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1527 Zone Atlantic/Bermuda -4:19:04 - LMT 1930 Jan 1 2:00 # Hamilton
1528 -4:00 - AST 1974 Apr 28 2:00
1529 -4:00 Bahamas A%sT
1531 # Cayman Is
1532 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1533 Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown
1534 -5:07:12 - KMT 1912 Feb # Kingston Mean Time
1535 -5:00 - EST
1537 # Costa Rica
1538 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1539 Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D
1540 Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S
1541 Rule CR 1991 1992 - Jan Sat>=15 0:00 1:00 D
1542 # IATA SSIM (1991-09) says the following was at 1:00; go with Shanks.
1543 Rule CR 1991 only - Jul 1 0:00 0 S
1544 Rule CR 1992 only - Mar 15 0:00 0 S
1545 # There are too many San Joses elsewhere, so we'll use `Costa Rica'.
1546 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1547 Zone America/Costa_Rica -5:36:20 - LMT 1890 # San Jose
1548 -5:36:20 - SJMT 1921 Jan 15 # San Jose Mean Time
1549 -6:00 CR C%sT
1550 # Coco
1551 # no information; probably like America/Costa_Rica
1553 # Cuba
1555 # From Arthur David Olson (1999-03-29):
1556 # The 1999-03-28 exhibition baseball game held in Havana, Cuba, between
1557 # the Cuban National Team and the Baltimore Orioles was carried live on
1558 # the Orioles Radio Network, including affiliate WTOP in Washington, DC.
1559 # During the game, play-by-play announcer Jim Hunter noted that
1560 # "We'll be losing two hours of sleep...Cuba switched to Daylight Saving
1561 # Time today." (The "two hour" remark referred to losing one hour of
1562 # sleep on 1999-03-28--when the announcers were in Cuba as it switched
1563 # to DST--and one more hour on 1999-04-04--when the announcers will have
1564 # returned to Baltimore, which switches on that date.)
1566 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1567 Rule Cuba 1928 only - Jun 10 0:00 1:00 D
1568 Rule Cuba 1928 only - Oct 10 0:00 0 S
1569 Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D
1570 Rule Cuba 1940 1942 - Sep Sun>=1 0:00 0 S
1571 Rule Cuba 1945 1946 - Jun Sun>=1 0:00 1:00 D
1572 Rule Cuba 1945 1946 - Sep Sun>=1 0:00 0 S
1573 Rule Cuba 1965 only - Jun 1 0:00 1:00 D
1574 Rule Cuba 1965 only - Sep 30 0:00 0 S
1575 Rule Cuba 1966 only - May 29 0:00 1:00 D
1576 Rule Cuba 1966 only - Oct 2 0:00 0 S
1577 Rule Cuba 1967 only - Apr 8 0:00 1:00 D
1578 Rule Cuba 1967 1968 - Sep Sun>=8 0:00 0 S
1579 Rule Cuba 1968 only - Apr 14 0:00 1:00 D
1580 Rule Cuba 1969 1977 - Apr lastSun 0:00 1:00 D
1581 Rule Cuba 1969 1971 - Oct lastSun 0:00 0 S
1582 Rule Cuba 1972 1974 - Oct 8 0:00 0 S
1583 Rule Cuba 1975 1977 - Oct lastSun 0:00 0 S
1584 Rule Cuba 1978 only - May 7 0:00 1:00 D
1585 Rule Cuba 1978 1990 - Oct Sun>=8 0:00 0 S
1586 Rule Cuba 1979 1980 - Mar Sun>=15 0:00 1:00 D
1587 Rule Cuba 1981 1985 - May Sun>=5 0:00 1:00 D
1588 Rule Cuba 1986 1989 - Mar Sun>=14 0:00 1:00 D
1589 Rule Cuba 1990 1997 - Apr Sun>=1 0:00 1:00 D
1590 Rule Cuba 1991 1995 - Oct Sun>=8 0:00s 0 S
1591 Rule Cuba 1996 only - Oct 6 0:00s 0 S
1592 Rule Cuba 1997 only - Oct 12 0:00s 0 S
1593 Rule Cuba 1998 1999 - Mar lastSun 0:00s 1:00 D
1594 Rule Cuba 1998 max - Oct lastSun 0:00s 0 S
1595 Rule Cuba 2000 max - Apr Sun>=1 0:00s 1:00 D
1597 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1598 Zone America/Havana -5:29:28 - LMT 1890
1599 -5:29:36 - HMT 1925 Jul 19 12:00 # Havana MT
1600 -5:00 Cuba C%sT
1602 # Dominica
1603 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1604 Zone America/Dominica -4:05:36 - LMT 1911 Jul 1 0:01 # Roseau
1605 -4:00 - AST
1607 # Dominican Republic
1609 # From Steffen Thorsen (2000-10-30):
1610 # Enrique Morales reported to me that the Dominican Republic has changed the
1611 # time zone to Eastern Standard Time as of Sunday 29 at 2 am....
1612 # http://www.listin.com.do/antes/261000/republica/princi.html
1614 # From Paul Eggert (2000-12-04):
1615 # That URL (2000-10-26, in Spanish) says they planned to use US-style DST.
1617 # From Rives McDow (2000-12-01):
1618 # Dominican Republic changed its mind and presidential decree on Tuesday,
1619 # November 28, 2000, with a new decree. On Sunday, December 3 at 1:00 AM the
1620 # Dominican Republic will be reverting to 8 hours from the International Date
1621 # Line, and will not be using DST in the foreseeable future. The reason they
1622 # decided to use DST was to be in synch with Puerto Rico, who was also going
1623 # to implement DST. When Puerto Rico didn't implement DST, the president
1624 # decided to revert.
1627 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1628 Rule DR 1966 only - Oct 30 0:00 1:00 D
1629 Rule DR 1967 only - Feb 28 0:00 0 S
1630 Rule DR 1969 1973 - Oct lastSun 0:00 0:30 HD
1631 Rule DR 1970 only - Feb 21 0:00 0 S
1632 Rule DR 1971 only - Jan 20 0:00 0 S
1633 Rule DR 1972 1974 - Jan 21 0:00 0 S
1634 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1635 Zone America/Santo_Domingo -4:39:36 - LMT 1890
1636 -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT
1637 -5:00 DR E%sT 1974 Oct 27
1638 -4:00 - AST 2000 Oct 29 02:00
1639 -5:00 US E%sT 2000 Dec 3 01:00
1640 -4:00 - AST
1642 # El Salvador
1643 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1644 Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D
1645 Rule Salv 1987 1988 - Sep lastSun 0:00 0 S
1646 # There are too many San Salvadors elsewhere, so we'll use `El Salvador'.
1647 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1648 Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador
1649 -6:00 Salv C%sT
1651 # Grenada
1652 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1653 Zone America/Grenada -4:07:00 - LMT 1911 Jul # St George's
1654 -4:00 - AST
1656 # Guadeloupe
1657 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1658 Zone America/Guadeloupe -4:06:08 - LMT 1911 Jun 8 # Pointe a Pitre
1659 -4:00 - AST
1661 # Guatemala
1662 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1663 Rule Guat 1973 only - Nov 25 0:00 1:00 D
1664 Rule Guat 1974 only - Feb 24 0:00 0 S
1665 Rule Guat 1983 only - May 21 0:00 1:00 D
1666 Rule Guat 1983 only - Sep 22 0:00 0 S
1667 Rule Guat 1991 only - Mar 23 0:00 1:00 D
1668 Rule Guat 1991 only - Sep 7 0:00 0 S
1669 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1670 Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5
1671 -6:00 Guat C%sT
1673 # Haiti
1674 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1675 Rule Haiti 1983 only - May 8 0:00 1:00 D
1676 Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D
1677 Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S
1678 # Shanks says AT is 2:00, but IATA SSIM (1991/1997) says 1:00s. Go with IATA.
1679 Rule Haiti 1988 1997 - Apr Sun>=1 1:00s 1:00 D
1680 Rule Haiti 1988 1997 - Oct lastSun 1:00s 0 S
1681 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1682 Zone America/Port-au-Prince -4:49:20 - LMT 1890
1683 -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT
1684 -5:00 Haiti E%sT
1686 # Honduras
1687 # Shanks says 1921 Jan 1; go with Whitman's more precise Apr 1.
1688 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1689 Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr
1690 -6:00 Salv C%sT
1691 #
1692 # Great Swan I ceded by US to Honduras in 1972
1694 # Jamaica
1696 # From Bob Devine (1988-01-28):
1697 # Follows US rules.
1699 # From U. S. Naval Observatory (1989-01-19):
1700 # JAMAICA 5 H BEHIND UTC
1702 # From Shanks:
1703 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1704 Zone America/Jamaica -5:07:12 - LMT 1890 # Kingston
1705 -5:07:12 - KMT 1912 Feb # Kingston Mean Time
1706 -5:00 - EST 1974 Apr 28 2:00
1707 -5:00 US E%sT 1984
1708 -5:00 - EST
1710 # Martinique
1711 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1712 Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France
1713 -4:04:20 - FFMT 1911 May # Fort-de-France MT
1714 -4:00 - AST 1980 Apr 6
1715 -4:00 1:00 ADT 1980 Sep 28
1716 -4:00 - AST
1718 # Montserrat
1719 # From Paul Eggert (1997-08-31):
1720 # Recent volcanic eruptions have forced evacuation of Plymouth, the capital.
1721 # Luckily, Olveston, the current de facto capital, has the same longitude.
1722 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1723 Zone America/Montserrat -4:08:52 - LMT 1911 Jul 1 0:01 # Olveston
1724 -4:00 - AST
1726 # Nicaragua
1727 #
1728 # From Steffen Thorsen (1998-12-29):
1729 # Nicaragua seems to be back at -6:00 but I have not been able to find when
1730 # they changed from -5:00.
1731 #
1732 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1733 Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D
1734 Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S
1735 Rule Nic 1992 only - Jan 1 4:00 1:00 D
1736 Rule Nic 1992 only - Sep 24 0:00 0 S
1737 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1738 Zone America/Managua -5:45:08 - LMT 1890
1739 -5:45:12 - MMT 1934 Jun 23 # Managua Mean Time?
1740 -6:00 - CST 1973 May
1741 -5:00 - EST 1975 Feb 16
1742 -6:00 Nic C%sT 1993 Jan 1 4:00
1743 -5:00 - EST 1998 Dec
1744 -6:00 - CST
1746 # Panama
1747 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1748 Zone America/Panama -5:18:08 - LMT 1890
1749 -5:19:36 - CMT 1908 Apr 22 # Colon Mean Time
1750 -5:00 - EST
1752 # Puerto Rico
1753 # There are too many San Juans elsewhere, so we'll use `Puerto_Rico'.
1754 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1755 Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan
1756 -4:00 - AST 1942 May 3
1757 -4:00 1:00 AWT 1945 Sep 30 2:00
1758 -4:00 - AST
1760 # St Kitts-Nevis
1761 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1762 Zone America/St_Kitts -4:10:52 - LMT 1912 Mar 2 # Basseterre
1763 -4:00 - AST
1765 # St Lucia
1766 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1767 Zone America/St_Lucia -4:04:00 - LMT 1890 # Castries
1768 -4:04:00 - CMT 1912 # Castries Mean Time
1769 -4:00 - AST
1771 # St Pierre and Miquelon
1772 # There are too many St Pierres elsewhere, so we'll use `Miquelon'.
1773 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1774 Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre
1775 -4:00 - AST 1980 May
1776 -3:00 Mont PM%sT # Pierre & Miquelon Time
1778 # St Vincent and the Grenadines
1779 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1780 Zone America/St_Vincent -4:04:56 - LMT 1890 # Kingstown
1781 -4:04:56 - KMT 1912 # Kingstown Mean Time
1782 -4:00 - AST
1784 # Turks and Caicos
1785 # From Paul Eggert (1998-08-06):
1786 # Shanks says they use US DST rules, but IATA SSIM (1991/1998)
1787 # says they switch at midnight. Go with IATA SSIM.
1788 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1789 Rule TC 1979 1986 - Apr lastSun 0:00 1:00 D
1790 Rule TC 1979 max - Oct lastSun 0:00 0 S
1791 Rule TC 1987 max - Apr Sun>=1 0:00 1:00 D
1792 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1793 Zone America/Grand_Turk -4:44:32 - LMT 1890
1794 -5:07:12 - KMT 1912 Feb # Kingston Mean Time
1795 -5:00 TC E%sT
1797 # British Virgin Is
1798 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1799 Zone America/Tortola -4:18:28 - LMT 1911 Jul # Road Town
1800 -4:00 - AST
1802 # Virgin Is
1803 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1804 Zone America/St_Thomas -4:19:44 - LMT 1911 Jul # Charlotte Amalie
1805 -4:00 - AST