1 # @(#)southamerica 7.25
3 # This data is by no means authoritative; if you think you know better,
4 # go ahead and edit the file (and please send any changes to
5 # tz@elsie.nci.nih.gov for general use in the future).
7 # From Paul Eggert <eggert@twinsun.com> (1996-11-22):
8 # A good source for time zone historical data outside the U.S. is
9 # Thomas G. Shanks, The International Atlas (4th edition),
10 # San Diego: ACS Publications, Inc. (1995).
12 # Gwillim Law <LAW@encmail.encompass.com> writes that a good source
13 # for recent time zone data is the International Air Transport
14 # Association's Standard Schedules Information Manual (IATA SSIM),
15 # published semiannually. Law sent in several helpful summaries
16 # of the IATA's data after 1990.
18 # Except where otherwise noted, Shanks is the source for entries through 1990,
19 # and IATA SSIM is the source for entries after 1990.
21 # The following abbreviations are used in this file.
22 # Corrections are welcome!
25 # -2:00 FST FDT Fernando de Noronha
26 # -3:00 EST EDT Eastern Brazil
27 # -4:00 WST WDT Western Brazil
28 # -4:00 AST ADT Atlantic
31 # Earlier editions of these tables used the North American style (e.g. ARST and
32 # ARDT for Argentine Standard and Daylight Time), but the following quote
33 # suggests that it's better to use European style (e.g. ART and ARST).
34 # I suggest the use of _Summer time_ instead of the more cumbersome
35 # _daylight-saving time_. _Summer time_ seems to be in general use
36 # in Europe and South America.
37 # -- E O Cutler, _New York Times_ (1937-02-14), quoted in
38 # H L Mencken, _The American Language: Supplement I_ (1960), p 466
42 # From Official Airline Guide - Worldwide Edition (1987). Countries not
43 # listed here do not observe DST, according to the OAG. Time zone names
44 # are pure inventions, and none are supplied for countries not observing
45 # DST; updates from natives would be appreciated. The times that DST
46 # starts and ends are based on the assumption that they switch a 2AM just
47 # as everybody else does.
49 ###############################################################################
51 ###############################################################################
55 # From Bob Devine (1988-01-28):
56 # Argentina: first Sunday in October to first Sunday in April since 1976.
57 # Double Summer time from 1969 to 1974. Switches at midnight.
59 # From U. S. Naval Observatory (1988-01-199):
60 # ARGENTINA 3 H BEHIND UTC
62 # From Hernan G. Otero <hernan@isoft.com.ar> (1995-06-26):
63 # I am sending modifications to the Argentine time zone table...
64 # AR was chosen because they are the ISO letters that represent Argentina.
66 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
67 Rule Arg 1930 only - Dec 1 0:00 1:00 S
68 Rule Arg 1931 only - Apr 1 0:00 0 -
69 Rule Arg 1931 only - Oct 15 0:00 1:00 S
70 Rule Arg 1932 1940 - Mar 1 0:00 0 -
71 Rule Arg 1932 1939 - Nov 1 0:00 1:00 S
72 Rule Arg 1940 only - Jul 1 0:00 1:00 S
73 Rule Arg 1941 only - Jun 15 0:00 0 -
74 Rule Arg 1941 only - Oct 15 0:00 1:00 S
75 Rule Arg 1943 only - Aug 1 0:00 0 -
76 Rule Arg 1943 only - Oct 15 0:00 1:00 S
77 Rule Arg 1946 only - Mar 1 0:00 0 -
78 Rule Arg 1946 only - Oct 1 0:00 1:00 S
79 Rule Arg 1963 only - Oct 1 0:00 0 -
80 Rule Arg 1963 only - Dec 15 0:00 1:00 S
81 Rule Arg 1964 1966 - Mar 1 0:00 0 -
82 Rule Arg 1964 1966 - Oct 15 0:00 1:00 S
83 Rule Arg 1967 only - Apr 1 0:00 0 -
84 Rule Arg 1967 1968 - Oct Sun<=7 0:00 1:00 S
85 Rule Arg 1968 1969 - Apr Sun<=7 0:00 0 -
86 Rule Arg 1974 only - Jan 23 0:00 1:00 S
87 Rule Arg 1974 only - May 1 0:00 0 -
88 Rule Arg 1974 1976 - Oct Sun<=7 0:00 1:00 S
89 Rule Arg 1975 1977 - Apr Sun<=7 0:00 0 -
90 Rule Arg 1985 only - Nov 2 0:00 1:00 S
91 Rule Arg 1986 only - Mar 14 0:00 0 -
92 Rule Arg 1986 1987 - Oct 25 0:00 1:00 S
93 Rule Arg 1987 only - Feb 13 0:00 0 -
94 Rule Arg 1988 only - Feb 7 0:00 0 -
95 Rule Arg 1988 only - Dec 1 0:00 1:00 S
97 # From Hernan G. Otero <hernan@isoft.com.ar> (1995-06-26):
98 # These corrections were contributed by InterSoft Argentina S.A.,
99 # obtaining the data from the:
100 # Talleres de Hidrografia Naval Argentina
101 # (Argentine Naval Hydrography Institute)
103 # Shanks gives 1989 Mar 16 and stops after 1990 Mar 4; go with Otero.
104 Rule Arg 1989 1993 - Mar Sun>=1 0:00 0 -
105 Rule Arg 1989 1992 - Oct Sun>=15 0:00 1:00 S
107 # From Hernan G. Otero <hernan@isoft.com.ar> (1995-06-26):
108 # From this moment on, the law that mandated the daylight saving
109 # time corrections was derogated and no more modifications
110 # to the time zones (for daylight saving) are now made.
112 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
114 # Buenos Aires (BA), Distrito Federal (DF), Santa Cruz (SC),
115 # Tierra del Fuego (TF) & Antartida e Islas
116 Zone America/Buenos_Aires -3:53:48 - LMT 1894 Nov
117 -4:16:44 - CMT 1920 May # Cordoba Mean Time
119 -4:00 Arg AR%sT 1969 Oct 5
122 # Santa Fe (SF), Entre Rios (ER), Corrientes (CN), Misiones (MN), Chaco (CC),
123 # Formosa (FM), La Pampa (LP), Chubut (CH)
124 Zone America/Rosario -4:02:40 - LMT 1894 Nov
125 -4:16:44 - CMT 1920 May
127 -4:00 Arg AR%sT 1969 Oct 5
128 -3:00 Arg AR%sT 1991 Jul
131 # Cordoba (CB), Santiago del Estero (SE), Salta (SA), Tucuman (TM), La Rioja (LR), San Juan (SJ), San Luis (SL),
132 # Neuquen (NQ), Rio Negro (RN)
133 Zone America/Cordoba -4:16:44 - LMT 1894 Nov
134 -4:16:44 - CMT 1920 May
136 -4:00 Arg AR%sT 1969 Oct 5
137 -3:00 Arg AR%sT 1990 Jul
141 Zone America/Jujuy -4:21:12 - LMT 1894 Nov
142 -4:16:44 - CMT 1920 May
144 -4:00 Arg AR%sT 1969 Oct 5
145 -3:00 Arg AR%sT 1991 Mar 3
146 -4:00 - WART 1991 Oct 6
147 -4:00 1:00 WARST 1992 Mar 15
148 -4:00 - WART 1992 Oct 18
152 Zone America/Catamarca -4:23:08 - LMT 1894 Nov
153 -4:16:44 - CMT 1920 May
155 -4:00 Arg AR%sT 1969 Oct 5
156 -3:00 Arg AR%sT 1990 Jul
158 -3:00 Arg AR%sT 1992 Jul
162 Zone America/Mendoza -4:35:16 - LMT 1894 Nov
163 -4:16:44 - CMT 1920 May
165 -4:00 Arg AR%sT 1969 Oct 5
166 -3:00 Arg AR%sT 1991 Mar 3
167 -4:00 - WART 1991 Oct 15
168 -4:00 1:00 WARST 1992 Mar 1
169 -4:00 - WART 1992 Oct 18
173 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
174 Zone America/Aruba -4:40:24 - LMT 1912 Feb 12 # Oranjestad
175 -4:30 - ANT 1965 # Netherlands Antilles Time
179 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
180 Zone America/La_Paz -4:32:36 - LMT 1890
181 -4:32:36 - LPMT 1931 Oct 15 # La Paz Mean Time
182 -4:32:36 1:00 BOST 1932 Mar 21 # Bolivia ST
183 -4:00 - BOT # Bolivia Time
187 # From Paul Eggert <eggert@twinsun.com> (1993-11-18):
188 # The mayor of Rio recently attempted to change the time zone rules
189 # just in his city, in order to leave more summer time for the tourist trade.
190 # The rule change lasted only part of the day;
191 # the federal government refused to follow the city's rules, and business
192 # was in a chaos, so the mayor backed down that afternoon.
194 # From IATA SSIM (1996-02):
195 # _Only_ the following states in BR1 observe DST: Rio Grande do Sul (RS),
196 # Santa Catarina (SC), Parana (PR), Sao Paulo (SP), Rio de Janeiro (RJ),
197 # Espirito Santo (ES), Minas Gerais (MG), Bahia (BA), Goias (GO),
198 # Distrito Federal (DF), Tocantins (TO), Sergipe [SE] and Alagoas [AL].
199 # [The last three states are new to this issue of the IATA SSIM.]
201 # From Gwillim Law (1996-10-07):
202 # Geography, history (Tocantins was part of Goias until 1989), and other
203 # sources of time zone information lead me to believe that AL, SE, and TO were
204 # always in BR1, and so the only change was whether or not they observed DST....
205 # The earliest issue of the SSIM I have is 2/91. Each issue from then until
206 # 9/95 says that DST is observed only in the ten states I quoted from 9/95,
207 # along with Mato Grosso (MT) and Mato Grosso do Sul (MS), which are in BR2
208 # (UTC-4).... The other two time zones given for Brazil are BR3, which is
209 # UTC-5, no DST, and applies only in the state of Acre (AC); and BR4, which is
210 # UTC-2, and applies to Fernando de Noronha (formerly FN, but I believe it's
211 # become part of the state of Pernambuco). The boundary between BR1 and BR2
212 # has never been clearly stated. They've simply been called East and West.
213 # However, some conclusions can be drawn from another IATA manual: the Airline
214 # Coding Directory, which lists close to 400 airports in Brazil. For each
215 # airport it gives a time zone which is coded to the SSIM. From that
216 # information, I'm led to conclude that the states of Amapa (AP), Ceara (CE),
217 # Maranhao (MA), Paraiba (PR), Pernambuco (PE), Piaui (PI), and Rio Grande do
218 # Norte (RN), and the eastern part of Para (PA) are all in BR1 without DST.
220 # From Paul Eggert (1996-11-22):
221 # Let's make the following assumptions:
223 # * All data in Shanks are correct through 1990. In particular,
224 # Shanks was right when he said Acre stopped observing DST in mid-1988.
225 # * Areas where Shanks reports DST up to 1990, but the IATA reports no DST
226 # in 1995, stopped observing DST in mid-1990.
228 # Under these assumptions Brazil needs 7 entries to cover all the distinct
229 # time zone histories since 1970:
231 # Noronha (UTC-2), Fortaleza (UTC-3), and Manaus (UTC-4) stopped observing DST
233 # Maceio (UTC-3) stopped observing DST in mid-1990, but started again mid-1995.
234 # Sao Paulo (UTC-3) and Cuiaba (UTC-4) always observed DST.
235 # Porto Acre (UTC-5) stopped observing DST in mid-1988.
237 # From Rodrigo Feher <feher@pobox.com> (1998-01-17):
238 # Reading "southamerica" file in timezone 7.55 I've found an
239 # error. Line 193 say "Territory of Acre". It is not a territory anymore
242 # From Marcos Tadeu (1998-09-27):
243 # <a href="http://pcdsh01.on.br/verao1.html">
244 # Brazilian official page
247 # From Paul Eggert (1998-09-28):
248 # The official decrees referenced below are taken from
249 # <a href="http://pcdsh01.on.br/DecHV.html">
250 # Decretos sobre o Horario de Verao no Brasil
251 # </a> (1998-09-25, in Portuguese).
252 # I don't read Portuguese, and haven't been able to verify them against
253 # the Shanks and IATA data; there do seem to be minor discrepancies.
255 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
256 # Decree <a href="http://pcdsh01.on.br/HV20466.htm">20.466</a> (1931-01-10)
257 # Decree <a href="http://pcdsh01.on.br/HV21896.htm">21.896</a> (1932-01-10)
258 Rule Brazil 1931 only - Oct 3 11:00 1:00 D
259 Rule Brazil 1932 1933 - Apr 1 0:00 0 S
260 Rule Brazil 1932 only - Oct 3 0:00 1:00 D
261 # Decree <a href="http://pcdsh01.on.br/HV23195.htm">23.195</a> (1933-10-10)
263 # Decree <a href="http://pcdsh01.on.br/HV27496.htm">27.496</a> (1949-11-24)
264 # Decree <a href="http://pcdsh01.on.br/HV27998.htm">27.998</a> (1950-04-13)
265 # Decree <a href="http://pcdsh01.on.br/HV32308.htm">32.308</a> (1953-02-24)
266 Rule Brazil 1949 1952 - Dec 1 0:00 1:00 D
267 Rule Brazil 1950 only - Apr 16 0:00 0 S
268 Rule Brazil 1951 1953 - Apr 1 0:00 0 S
269 # Decree <a href="http://pcdsh01.on.br/HV34724.htm">34.724</a> (1953-11-30)
271 # Decree <a href="http://pcdsh01.on.br/HV52700.htm">52.700</a> (1963-10-18)
272 # Decree <a href="http://pcdsh01.on.br/HV53071.htm">53.071</a> (1963-12-03)
273 Rule Brazil 1963 only - Dec 9 0:00 1:00 D
274 # Decree <a href="http://pcdsh01.on.br/HV53604.htm">53.604</a> (1964-02-25)
275 Rule Brazil 1964 only - Mar 1 0:00 0 S
276 # Decree <a href="http://pcdsh01.on.br/HV55639.htm">55.639</a> (1965-01-27)
277 Rule Brazil 1965 only - Jan 31 0:00 1:00 D
278 Rule Brazil 1965 only - Apr 1 0:00 0 S
279 # Decree <a href="http://pcdsh01.on.br/HV57303.htm">57.303</a> (1965-11-22)
280 Rule Brazil 1965 only - Dec 1 0:00 1:00 D
281 # Decree <a href="http://pcdsh01.on.br/HV57843.htm">57.843</a> (1966-02-18)
282 Rule Brazil 1966 1968 - Mar 1 0:00 0 S
283 Rule Brazil 1966 1967 - Nov 1 0:00 1:00 D
284 # Decree <a href="http://pcdsh01.on.br/HV63429.htm">63.429</a> (1968-10-15)
285 # Decree <a href="http://pcdsh01.on.br/HV91698.htm">91.698</a> (1985-09-27)
286 Rule Brazil 1985 only - Nov 2 0:00 1:00 D
287 # Decree 92.310 (1986-01-21)
288 # Decree 92.463 (1986-03-13)
289 Rule Brazil 1986 only - Mar 15 0:00 0 S
290 # Decree 93.316 (1986-10-01)
291 # Decree <a href="http://pcdsh01.on.br/HV94922.htm">94.922</a> (1987-09-22)
292 Rule Brazil 1986 1987 - Oct Sat<=28 0:00 1:00 D
293 Rule Brazil 1987 only - Feb 14 0:00 0 S
294 Rule Brazil 1988 only - Feb 7 0:00 0 S
295 # Decree <a href="http://pcdsh01.on.br/HV96676.htm">96.676</a> (1988-09-12)
296 # Decree <a href="http://pcdsh01.on.br/HV98077.htm">98.077</a> (1989-08-21)
297 # Decree <a href="http://pcdsh01.on.br/HV99530.htm">99.530</a> (1990-09-17)
298 # Decree 99.629 (1990-10-19)
299 # <a href="http://pcdsh01.on.br/HV1991.htm">Unnumbered decree</a> (1991-09-25):
300 # <a href="http://pcdsh01.on.br/HV1992.htm">Unnumbered decree</a> (1992-10-16):
301 Rule Brazil 1989 only - Jan 22 0:00 0 S
302 Rule Brazil 1988 1989 - Oct Sun>=10 0:00 1:00 D
303 Rule Brazil 1990 1991 - Feb Sun>=11 0:00 0 S
304 Rule Brazil 1990 1992 - Oct Sun>=20 0:00 1:00 D
305 Rule Brazil 1992 only - Feb 9 0:00 0 S
306 # Decree <a href="http://pcdsh01.on.br/HV942.htm">942</a> (1993-09-28)
307 # Decree <a href="http://pcdsh01.on.br/HV1252.htm">1.252</a> (1994-09-22)
308 # Decree <a href="http://pcdsh01.on.br/HV1636.htm">1.636</a> (1995-09-14)
309 # Decree <a href="http://pcdsh01.on.br/HV1674.htm">1.674</a> (1995-10-13)
310 Rule Brazil 1993 1995 - Oct Sun>=11 0:00 1:00 D
311 Rule Brazil 1993 only - Jan 31 0:00 0 S
312 Rule Brazil 1994 1995 - Feb Sun>=15 0:00 0 S
313 # Decree <a href="http://pcdsh01.on.br/HV2000.htm">2.000</a> (1996-09-04)
314 Rule Brazil 1996 only - Feb Sun>=11 0:00 0 S
315 Rule Brazil 1996 only - Oct Sun>=1 0:00 1:00 D
316 # From Daniel C. Sobral <dcs@gns.com.br> (1998-02-12):
317 # In 1997, the DS began on October 6. The stated reason was that
318 # because international television networks ignored Brazil's policy on DS,
319 # they bought the wrong times on satellite for coverage of Pope's visit.
320 # This year, the ending date of DS was postponed to March 1
321 # to help dealing with the shortages of electric power.
323 # From Paul Eggert (1998-02-25):
324 # <a href="http://churchnet.ucsm.ac.uk/news/files2/news165.htm">
325 # Brazil Prepares for Papal Visit
327 # Church Net UK (1997-10-02).
329 # Decree 2.317 (1997-09-04)
330 Rule Brazil 1997 only - Oct 6 0:00 1:00 D
331 # Decree <a href="http://pcdsh01.on.br/figuras/HV2495.JPG">2.495</a>
333 Rule Brazil 1998 only - Mar 1 0:00 0 S
334 # Decree <a href="http://pcdsh01.on.br/figuras/Hv98.jpg">2.780</a> (1998-09-11)
335 # specifies only the 1998-10-11 and 1999-02-21 transitions;
336 # after that, these rules are guesses and are quite possibly wrong,
337 # but they are more likely than no DST at all.
338 Rule Brazil 1998 max - Oct Sun>=11 0:00 1:00 D
339 Rule Brazil 1999 max - Feb Sun>=15 0:00 0 S
342 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
344 # Fernando de Noronha
345 Zone America/Noronha -2:09:40 - LMT 1914
346 -2:00 - FST 1963 Dec 9
347 -2:00 Brazil F%sT 1990 Jul
350 # Amapa, east Para, Maranhao, Piaui, Ceara, Rio Grande do Norte, Paraiba,
351 # Pernambuco (except Fernando de Noronha)
352 Zone America/Fortaleza -2:34:00 - LMT 1914
353 -3:00 - EST 1963 Dec 9
354 -3:00 Brazil E%sT 1990 Jul
357 # Alagoas, Sergipe, Tocantins
358 # IATA SSIM (1996/1998) keeps bouncing back and forth as to whether
359 # Alagoas and Sergipe observe DST. For now, continue to assume that they do.
360 Zone America/Maceio -2:22:52 - LMT 1914
361 -3:00 - EST 1963 Dec 9
362 -3:00 Brazil E%sT 1990 Jul
366 # Bahia, Goias, Distrito Federal, Minas Gerais, Espirito Santo, Rio de Janeiro,
367 # Sao Paulo, Parana, Santa Catarina, Rio Grande do Sul
368 Zone America/Sao_Paulo -3:06:28 - LMT 1914
371 # Mato Grosso, Mato Grosso do Sul
372 Zone America/Cuiaba -3:44:20 - LMT 1914
373 -4:00 - WST 1963 Dec 9
376 # Roraima, west Para, Amazonas, Rondonia
377 Zone America/Manaus -4:00:04 - LMT 1914
378 -4:00 - WST 1963 Dec 9
379 -4:00 Brazil W%sT 1990 Jul
383 # Rio_Branco is too ambiguous, since there's a Rio Branco in Uruguay too.
384 Zone America/Porto_Acre -4:31:12 - LMT 1914
385 -5:00 - AST 1963 Dec 9
386 -5:00 Brazil A%sT 1988 Jul
389 # Martin Vaz and Trinidade are like America/Noronha.
394 # From Eduardo Krell (1995-10-19):
395 # The law says to switch to DST at midnight [24:00] on the second SATURDAY
396 # of October.... The law is the same for March and October.
398 # Because of the drought this year, the government decided to go into
399 # DST earlier (saturday 9/26 at 24:00). This is a one-time change only ...
400 # (unless there's another dry season next year, I guess).
402 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
403 Rule Chile 1918 only - Sep 1 0:00 1:00 S
404 Rule Chile 1919 only - Jul 2 0:00 0 -
405 Rule Chile 1927 1931 - Sep 1 0:00 1:00 S
406 Rule Chile 1928 1932 - Apr 1 0:00 0 -
407 Rule Chile 1969 1997 - Oct Sun>=9 0:00 1:00 S
408 Rule Chile 1970 max - Mar Sun>=9 0:00 0 -
409 Rule Chile 1998 only - Sep 27 0:00 1:00 S
410 Rule Chile 1999 max - Oct Sun>=9 0:00 1:00 S
411 # IATA SSIM anomalies: (1990-09) says 1990-09-16; (1992-02) says 1992-03-14;
412 # (1996-09) says 1998-03-08. Ignore these for now.
413 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
414 Zone America/Santiago -4:42:40 - LMT 1890
415 -4:42:40 - SMT 1910 # Santiago Mean Time
416 -5:00 Chile CL%sT 1932 Sep # Chile Time
418 Zone Pacific/Easter -7:17:28 - LMT 1890 # Mataveri
419 -7:17:28 - MMT 1932 Sep # Mataveri Mean Time
420 -7:00 Chile EAS%sT 1982 Mar 14 # Easter I Time
423 # Whitman says Juan Fernandez Is are like America/Santiago.
424 # San Ambrosio, San Felix
425 # no information; probably like America/Santiago
429 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
430 Rule CO 1992 only - May 2 0:00 1:00 S
431 # Shanks (1995) estimates 1993-04-03 24:00 for this; go with IATA.
432 Rule CO 1992 only - Dec 31 0:00 0 -
433 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
434 Zone America/Bogota -4:56:20 - LMT 1884 Mar 13
435 -4:56:20 - BMT 1914 Nov 23 # Bogota Mean Time
436 -5:00 CO CO%sT # Colombia Time
437 # Malpelo, Providencia, San Andres
438 # no information; probably like America/Bogota
441 # Shanks (1995) says that Bottom and Oranjestad have been at -4:00 since
442 # standard time was introduced on 1912-03-02; and that Kralendijk and Rincon
443 # used Kralendijk Mean Time (-4:33:08) from 1912-02-02 to 1965-01-01.
444 # This all predates our 1970 cutoff, though.
445 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
446 Zone America/Curacao -4:35:44 - LMT 1912 Feb 12 # Willemstad
447 -4:30 - ANT 1965 # Netherlands Antilles Time
451 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
452 Zone America/Guayaquil -5:19:20 - LMT 1890
453 -5:14:00 - QMT 1931 # Quito Mean Time
454 -5:00 - ECT # Ecuador Time
455 Zone Pacific/Galapagos -5:58:24 - LMT 1931 # Puerto Baquerizo Moreno
457 -6:00 - GALT # Galapagos Time
460 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
461 Rule Falk 1937 1938 - Sep lastSun 0:00 1:00 S
462 Rule Falk 1938 1942 - Mar Sun>=19 0:00 0 -
463 Rule Falk 1939 only - Oct 1 0:00 1:00 S
464 Rule Falk 1940 1942 - Sep lastSun 0:00 1:00 S
465 Rule Falk 1943 only - Jan 1 0:00 0 -
466 Rule Falk 1983 only - Sep lastSun 0:00 1:00 S
467 Rule Falk 1984 1985 - Apr lastSun 0:00 0 -
468 Rule Falk 1984 only - Sep 16 0:00 1:00 S
469 Rule Falk 1985 1995 - Sep Sun>=9 0:00 1:00 S
470 Rule Falk 1986 max - Apr Sun>=16 0:00 0 -
471 Rule Falk 1996 max - Sep Sun>=8 0:00 1:00 S
472 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
473 Zone Atlantic/Stanley -3:51:24 - LMT 1890
474 -3:51:24 - SMT 1912 Mar 12 # Stanley Mean Time
475 -4:00 Falk FK%sT 1983 May # Falkland Is Time
476 -3:00 Falk FK%sT 1985 Sep 15
480 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
481 Zone America/Cayenne -3:29:20 - LMT 1911 Jul
482 -4:00 - GFT 1967 Oct # French Guiana Time
486 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
487 Zone America/Guyana -3:52:40 - LMT 1915 Mar # Georgetown
488 -3:45 - GBGT 1966 May 26 # Br Guiana Time
489 -3:45 - GYT 1975 Jul 31 # Guyana Time
491 # IATA SSIM (1996-06) says -4:00. Assume a 1991 switch.
496 # From Bob Devine (1988-01-28):
497 # Paraguay: First day in October to last in March. Midnight switch??
500 # From U. S. Naval Observatory (1989-01-19):
501 # PARAGUAY 4 H BEHIND UTC
502 # PARAGUAY 3 H BEHIND UTC OCT 1, '88-MAR 31, '89
504 # From Shanks (1991):
505 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
506 Rule Para 1975 1978 - Oct 1 0:00 1:00 S
507 Rule Para 1975 1978 - Mar 1 0:00 0 -
508 # Shanks says 1979 was all DST.
509 Rule Para 1980 1991 - Apr 1 0:00 0 -
510 Rule Para 1980 1988 - Oct 1 0:00 1:00 S
511 Rule Para 1989 only - Oct 22 0:00 1:00 S
512 Rule Para 1990 only - Oct 1 0:00 1:00 S
513 Rule Para 1991 only - Oct 6 0:00 1:00 S
514 Rule Para 1992 only - Mar 1 0:00 0 -
515 Rule Para 1992 only - Oct 5 0:00 1:00 S
516 Rule Para 1993 only - Mar 31 0:00 0 -
517 Rule Para 1993 1995 - Oct 1 0:00 1:00 S
518 Rule Para 1994 1995 - Feb lastSun 0:00 0 -
519 Rule Para 1996 1998 - Mar 1 0:00 0 -
520 Rule Para 1996 max - Oct Sun>=1 0:00 1:00 S
521 # IATA SSIM (1998-02) claims that the 1999 switch will be on 02-27.
522 # Assume this is a typo, and that 02-28 was meant.
523 Rule Para 1999 max - Feb lastSun 0:00 0 -
524 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
525 Zone America/Asuncion -3:50:40 - LMT 1890
526 -3:50:40 - AMT 1931 Oct 10 # Asuncion Mean Time
527 -4:00 - PYT 1972 Oct # Paraguay Time
532 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
533 Rule Peru 1938 only - Jan 1 0:00 1:00 S
534 Rule Peru 1938 only - Apr 1 0:00 0 -
535 Rule Peru 1938 1939 - Sep lastSun 0:00 1:00 S
536 Rule Peru 1939 1940 - Mar Sun>=24 0:00 0 -
537 Rule Peru 1987 only - Jan 1 0:00 1:00 S
538 Rule Peru 1987 only - Apr 1 0:00 0 -
539 Rule Peru 1990 only - Jan 1 0:00 1:00 S
540 Rule Peru 1990 only - Apr 1 0:00 0 -
541 Rule Peru 1993 only - Jan 1 0:00 1:00 S
542 Rule Peru 1993 only - Apr 1 0:00 0 -
543 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
544 Zone America/Lima -5:08:12 - LMT 1890
545 -5:09 - LMT 1908 Jul 28 # Lima Mean Time
546 -5:00 Peru PE%sT # Peru Time
549 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
550 Zone Atlantic/South_Georgia -2:26:08 - LMT 1890 # Grytviken
551 -2:00 - GST # South Georgia Time
557 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
558 Zone America/Paramaribo -3:40:40 - LMT 1911
559 -3:40:52 - PMT 1935 # Paramaribo Mean Time
560 -3:40:36 - PMT 1945 Oct # The capital moved?
561 -3:30 - NEGT 1975 Nov 20 # Dutch Guiana Time
562 -3:30 - SRT 1984 Oct # Suriname Time
565 # Trinidad and Tobago
566 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
567 Zone America/Port_of_Spain -4:06:04 - LMT 1912 Mar 2
571 # From Paul Eggert <eggert@twinsun.com> (1993-11-18):
572 # Uruguay wins the prize for the strangest peacetime manipulation of the rules.
573 # From Shanks (1991):
574 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
575 # Whitman gives 1923 Oct 1; go with Shanks.
576 Rule Uruguay 1923 only - Oct 2 0:00 0:30 HS
577 Rule Uruguay 1924 1926 - Apr 1 0:00 0 -
578 Rule Uruguay 1924 1925 - Oct 1 0:00 0:30 HS
579 Rule Uruguay 1933 1935 - Oct lastSun 0:00 0:30 HS
580 # Shanks gives 1935 Apr 1 0:00 and 1936 Mar 30 0:00; go with Whitman.
581 Rule Uruguay 1934 1936 - Mar Sat>=25 23:30s 0 -
582 Rule Uruguay 1936 only - Nov 1 0:00 0:30 HS
583 Rule Uruguay 1937 1941 - Mar lastSun 0:00 0 -
584 # Whitman gives 1937 Oct 3; go with Shanks.
585 Rule Uruguay 1937 1940 - Oct lastSun 0:00 0:30 HS
586 # Whitman gives 1941 Oct 24 - 1942 Mar 27, 1942 Dec 14 - 1943 Apr 13,
587 # and 1943 Apr 13 ``to present time''; go with Shanks.
588 Rule Uruguay 1941 only - Aug 1 0:00 0 -
589 Rule Uruguay 1942 only - Jan 1 0:00 0:30 HS
590 Rule Uruguay 1942 only - Dec 14 0:00 1:00 S
591 Rule Uruguay 1943 only - Mar 14 0:00 0 -
592 Rule Uruguay 1959 only - May 24 0:00 1:00 S
593 Rule Uruguay 1959 only - Nov 15 0:00 0 -
594 Rule Uruguay 1960 only - Jan 17 0:00 1:00 S
595 Rule Uruguay 1960 only - Mar 6 0:00 0 -
596 Rule Uruguay 1965 1967 - Apr Sun>=1 0:00 1:00 S
597 Rule Uruguay 1965 only - Sep 26 0:00 0 -
598 Rule Uruguay 1966 1967 - Oct 31 0:00 0 -
599 Rule Uruguay 1968 1970 - May 27 0:00 0:30 HS
600 Rule Uruguay 1968 1970 - Dec 2 0:00 0 -
601 Rule Uruguay 1972 only - Apr 24 0:00 1:00 S
602 Rule Uruguay 1972 only - Aug 15 0:00 0 -
603 Rule Uruguay 1974 only - Mar 10 0:00 0:30 HS
604 Rule Uruguay 1974 only - Dec 22 0:00 1:00 S
605 Rule Uruguay 1976 only - Oct 1 0:00 0 -
606 Rule Uruguay 1977 only - Dec 4 0:00 1:00 S
607 Rule Uruguay 1978 only - Apr 1 0:00 0 -
608 Rule Uruguay 1979 only - Oct 1 0:00 1:00 S
609 Rule Uruguay 1980 only - May 1 0:00 0 -
610 Rule Uruguay 1987 only - Dec 14 0:00 1:00 S
611 Rule Uruguay 1988 only - Mar 14 0:00 0 -
612 Rule Uruguay 1988 only - Dec 11 0:00 1:00 S
613 Rule Uruguay 1989 only - Mar 12 0:00 0 -
614 Rule Uruguay 1989 only - Oct 29 0:00 1:00 S
615 Rule Uruguay 1990 1992 - Mar Sun>=1 0:00 0 -
616 Rule Uruguay 1990 1991 - Oct Sun>=21 0:00 1:00 S
617 # Shanks's 4th edition (1995) says no DST was observed in 1990/1 and 1991/2,
618 # and that 1992/3's DST was from 10-25 to 03-01. Go with IATA.
619 Rule Uruguay 1992 only - Oct 18 0:00 1:00 S
620 Rule Uruguay 1993 only - Feb 28 0:00 0 -
621 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
622 Zone America/Montevideo -3:44:44 - LMT 1898 Jun 28
623 -3:44:44 - MMT 1920 May 1 # Montevideo MT
624 -3:30 Uruguay UY%sT 1942 Dec 14 # Uruguay Time
628 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
629 Zone America/Caracas -4:27:44 - LMT 1890
630 -4:27:44 - CMT 1912 Feb 12 # Caracas Mean Time
631 -4:30 - VET 1965 # Venezuela Time