# tzdb data for South America and environs # This file is in the public domain, so clarified as of # 2009-05-17 by Arthur David Olson. # This file is by no means authoritative; if you think you know better, # go ahead and edit the file (and please send any changes to # tz@iana.org for general use in the future). For more, please see # the file CONTRIBUTING in the tz distribution. # From Paul Eggert (2016-12-05): # # Unless otherwise specified, the source for data through 1990 is: # Thomas G. Shanks and Rique Pottenger, The International Atlas (6th edition), # San Diego: ACS Publications, Inc. (2003). # Unfortunately this book contains many errors and cites no sources. # # Many years ago Gwillim Law wrote that a good source # for time zone data was the International Air Transport # Association's Standard Schedules Information Manual (IATA SSIM), # published semiannually. Law sent in several helpful summaries # of the IATA's data after 1990. Except where otherwise noted, # IATA SSIM is the source for entries after 1990. # # For data circa 1899, a common source is: # Milne J. Civil time. Geogr J. 1899 Feb;13(2):173-94. # https://www.jstor.org/stable/1774359 # # These tables use numeric abbreviations like -03 and -0330 for # integer hour and minute UT offsets. Although earlier editions used # alphabetic time zone abbreviations, these abbreviations were # invented and did not reflect common practice. ############################################################################### ############################################################################### # Argentina # From Bob Devine (1988-01-28): # Argentina: first Sunday in October to first Sunday in April since 1976. # Double Summer time from 1969 to 1974. Switches at midnight. # From U. S. Naval Observatory (1988-01-19): # ARGENTINA 3 H BEHIND UTC # From Hernan G. Otero (1995-06-26): # I am sending modifications to the Argentine time zone table... # AR was chosen because they are the ISO letters that represent Argentina. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Arg 1930 only - Dec 1 0:00 1:00 - Rule Arg 1931 only - Apr 1 0:00 0 - Rule Arg 1931 only - Oct 15 0:00 1:00 - Rule Arg 1932 1940 - Mar 1 0:00 0 - Rule Arg 1932 1939 - Nov 1 0:00 1:00 - Rule Arg 1940 only - Jul 1 0:00 1:00 - Rule Arg 1941 only - Jun 15 0:00 0 - Rule Arg 1941 only - Oct 15 0:00 1:00 - Rule Arg 1943 only - Aug 1 0:00 0 - Rule Arg 1943 only - Oct 15 0:00 1:00 - Rule Arg 1946 only - Mar 1 0:00 0 - Rule Arg 1946 only - Oct 1 0:00 1:00 - Rule Arg 1963 only - Oct 1 0:00 0 - Rule Arg 1963 only - Dec 15 0:00 1:00 - Rule Arg 1964 1966 - Mar 1 0:00 0 - Rule Arg 1964 1966 - Oct 15 0:00 1:00 - Rule Arg 1967 only - Apr 2 0:00 0 - Rule Arg 1967 1968 - Oct Sun>=1 0:00 1:00 - Rule Arg 1968 1969 - Apr Sun>=1 0:00 0 - Rule Arg 1974 only - Jan 23 0:00 1:00 - Rule Arg 1974 only - May 1 0:00 0 - Rule Arg 1988 only - Dec 1 0:00 1:00 - # # From Hernan G. Otero (1995-06-26): # These corrections were contributed by InterSoft Argentina S.A., # obtaining the data from the: # Talleres de Hidrografía Naval Argentina # (Argentine Naval Hydrography Institute) Rule Arg 1989 1993 - Mar Sun>=1 0:00 0 - Rule Arg 1989 1992 - Oct Sun>=15 0:00 1:00 - # # From Hernan G. Otero (1995-06-26): # From this moment on, the law that mandated the daylight saving # time corrections was derogated and no more modifications # to the time zones (for daylight saving) are now made. # # From Rives McDow (2000-01-10): # On October 3, 1999, 0:00 local, Argentina implemented daylight savings time, # which did not result in the switch of a time zone, as they stayed 9 hours # from the International Date Line. Rule Arg 1999 only - Oct Sun>=1 0:00 1:00 - # From Paul Eggert (2007-12-28): # DST was set to expire on March 5, not March 3, but since it was converted # to standard time on March 3 it's more convenient for us to pretend that # it ended on March 3. Rule Arg 2000 only - Mar 3 0:00 0 - # # From Peter Gradelski via Steffen Thorsen (2000-03-01): # We just checked with our São Paulo office and they say the government of # Argentina decided not to become one of the countries that go on or off DST. # So Buenos Aires should be -3 hours from GMT at all times. # # From Fabián L. Arce Jofré (2000-04-04): # The law that claimed DST for Argentina was derogated by President Fernando # de la Rúa on March 2, 2000, because it would make people spend more energy # in the winter time, rather than less. The change took effect on March 3. # # From Mariano Absatz (2001-06-06): # one of the major newspapers here in Argentina said that the 1999 # Timezone Law (which never was effectively applied) will (would?) be # in effect.... The article is at # http://ar.clarin.com/diario/2001-06-06/e-01701.htm # ... The Law itself is "Ley No. 25155", sanctioned on 1999-08-25, enacted # 1999-09-17, and published 1999-09-21. The official publication is at: # http://www.boletin.jus.gov.ar/BON/Primera/1999/09-Septiembre/21/PDF/BO21-09-99LEG.PDF # Regretfully, you have to subscribe (and pay) for the on-line version.... # # (2001-06-12): # the timezone for Argentina will not change next Sunday. # Apparently it will do so on Sunday 24th.... # http://ar.clarin.com/diario/2001-06-12/s-03501.htm # # (2001-06-25): # Last Friday (yes, the last working day before the date of the change), the # Senate annulled the 1999 law that introduced the changes later postponed. # http://www.clarin.com.ar/diario/2001-06-22/s-03601.htm # It remains the vote of the Deputies..., but it will be the same.... # This kind of things had always been done this way in Argentina. # We are still -03:00 all year round in all of the country. # # From Steffen Thorsen (2007-12-21): # A user (Leonardo Chaim) reported that Argentina will adopt DST.... # all of the country (all Zone-entries) are affected. News reports like # http://www.lanacion.com.ar/opinion/nota.asp?nota_id=973037 indicate # that Argentina will use DST next year as well, from October to # March, although exact rules are not given. # # From Jesper Nørgaard Welen (2007-12-26) # The last hurdle of Argentina DST is over, the proposal was approved in # the lower chamber too (Diputados) with a vote 192 for and 2 against. # By the way thanks to Mariano Absatz and Daniel Mario Vega for the link to # the original scanned proposal, where the dates and the zero hours are # clear and unambiguous...This is the article about final approval: # http://www.lanacion.com.ar/politica/nota.asp?nota_id=973996 # # From Paul Eggert (2007-12-22): # For dates after mid-2008, the following rules are my guesses and # are quite possibly wrong, but are more likely than no DST at all. # From Alexander Krivenyshev (2008-09-05): # As per message from Carlos Alberto Fonseca Arauz (Nicaragua), # Argentina will start DST on Sunday October 19, 2008. # # http://www.worldtimezone.com/dst_news/dst_news_argentina03.html # http://www.impulsobaires.com.ar/nota.php?id=57832 (in spanish) # From Juan Manuel Docile in https://bugs.gentoo.org/240339 (2008-10-07) # via Rodrigo Severo: # Argentinian law No. 25.155 is no longer valid. # http://www.infoleg.gov.ar/infolegInternet/anexos/60000-64999/60036/norma.htm # The new one is law No. 26.350 # http://www.infoleg.gov.ar/infolegInternet/anexos/135000-139999/136191/norma.htm # So there is no summer time in Argentina for now. # From Mariano Absatz (2008-10-20): # Decree 1693/2008 applies Law 26.350 for the summer 2008/2009 establishing DST # in Argentina from 2008-10-19 until 2009-03-15. # http://www.boletinoficial.gov.ar/Bora.Portal/CustomControls/PdfContent.aspx?fp=16102008&pi=3&pf=4&s=0&sec=01 # # Decree 1705/2008 excepting 12 Provinces from applying DST in the summer # 2008/2009: Catamarca, La Rioja, Mendoza, Salta, San Juan, San Luis, La # Pampa, Neuquén, Rio Negro, Chubut, Santa Cruz and Tierra del Fuego # http://www.boletinoficial.gov.ar/Bora.Portal/CustomControls/PdfContent.aspx?fp=17102008&pi=1&pf=1&s=0&sec=01 # # Press release 235 dated Saturday October 18th, from the Government of the # Province of Jujuy saying it will not apply DST either (even when it was not # included in Decree 1705/2008). # http://www.jujuy.gov.ar/index2/partes_prensa/18_10_08/235-181008.doc # From fullinet (2009-10-18): # As announced in # http://www.argentina.gob.ar/argentina/portal/paginas.dhtml?pagina=356 # (an official .gob.ar) under title: "Sin Cambio de Hora" # (English: "No hour change"). # # "Por el momento, el Gobierno Nacional resolvió no modificar la hora # oficial, decisión que estaba en estudio para su implementación el # domingo 18 de octubre. Desde el Ministerio de Planificación se anunció # que la Argentina hoy, en estas condiciones meteorológicas, no necesita # la modificación del huso horario, ya que 2009 nos encuentra con # crecimiento en la producción y distribución energética." Rule Arg 2007 only - Dec 30 0:00 1:00 - Rule Arg 2008 2009 - Mar Sun>=15 0:00 0 - Rule Arg 2008 only - Oct Sun>=15 0:00 1:00 - # From Mariano Absatz (2004-05-21): # Today it was officially published that the Province of Mendoza is changing # its timezone this winter... starting tomorrow night.... # http://www.gobernac.mendoza.gov.ar/boletin/pdf/20040521-27158-normas.pdf # From Paul Eggert (2004-05-24): # It's Law No. 7,210. This change is due to a public power emergency, so for # now we'll assume it's for this year only. # # From Paul Eggert (2018-01-31): # Hora de verano para la República Argentina # http://buenasiembra.com.ar/esoterismo/astrologia/hora-de-verano-de-la-republica-argentina-27.html # says that standard time in Argentina from 1894-10-31 # to 1920-05-01 was -4:16:48.25. Go with this more-precise value # over Shanks & Pottenger. It is upward compatible with Milne, who # says Córdoba time was -4:16:48.2. # # From Mariano Absatz (2004-06-05): # These media articles from a major newspaper mostly cover the current state: # http://www.lanacion.com.ar/04/05/27/de_604825.asp # http://www.lanacion.com.ar/04/05/28/de_605203.asp # # The following eight (8) provinces pulled clocks back to UTC-04:00 at # midnight Monday May 31st. (that is, the night between 05/31 and 06/01). # Apparently, all nine provinces would go back to UTC-03:00 at the same # time in October 17th. # # Catamarca, Chubut, La Rioja, San Juan, San Luis, Santa Cruz, # Tierra del Fuego, Tucumán. # # From Mariano Absatz (2004-06-14): # ... this weekend, the Province of Tucumán decided it'd go back to UTC-03:00 # yesterday midnight (that is, at 24:00 Saturday 12th), since the people's # annoyance with the change is much higher than the power savings obtained.... # # From Gwillim Law (2004-06-14): # http://www.lanacion.com.ar/04/06/10/de_609078.asp ... # "The time change in Tierra del Fuego was a conflicted decision from # the start. The government had decreed that the measure would take # effect on June 1, but a normative error forced the new time to begin # three days earlier, from a Saturday to a Sunday.... # Our understanding was that the change was originally scheduled to take place # on June 1 at 00:00 in Chubut, Santa Cruz, Tierra del Fuego (and some other # provinces). Sunday was May 30, only two days earlier. So the article # contains a contradiction. I would give more credence to the Saturday/Sunday # date than the "three days earlier" phrase, and conclude that Tierra del # Fuego set its clocks back at 2004-05-30 00:00. # # From Steffen Thorsen (2004-10-05): # The previous law 7210 which changed the province of Mendoza's time zone # back in May have been modified slightly in a new law 7277, which set the # new end date to 2004-09-26 (original date was 2004-10-17). # http://www.gobernac.mendoza.gov.ar/boletin/pdf/20040924-27244-normas.pdf # # From Mariano Absatz (2004-10-05): # San Juan changed from UTC-03:00 to UTC-04:00 at midnight between # Sunday, May 30th and Monday, May 31st. It changed back to UTC-03:00 # at midnight between Saturday, July 24th and Sunday, July 25th.... # http://www.sanjuan.gov.ar/prensa/archivo/000329.html # http://www.sanjuan.gov.ar/prensa/archivo/000426.html # http://www.sanjuan.gov.ar/prensa/archivo/000441.html # From Alex Krivenyshev (2008-01-17): # Here are articles that Argentina Province San Luis is planning to end DST # as earlier as upcoming Monday January 21, 2008 or February 2008: # # Provincia argentina retrasa reloj y marca diferencia con resto del país # (Argentine Province delayed clock and mark difference with the rest of the # country) # http://cl.invertia.com/noticias/noticia.aspx?idNoticia=200801171849_EFE_ET4373&idtel # # Es inminente que en San Luis atrasen una hora los relojes # (It is imminent in San Luis clocks one hour delay) # https://www.lagaceta.com.ar/nota/253414/Economia/Es-inminente-que-en-San-Luis-atrasen-una-hora-los-relojes.html # http://www.worldtimezone.com/dst_news/dst_news_argentina02.html # From Jesper Nørgaard Welen (2008-01-18): # The page of the San Luis provincial government # http://www.sanluis.gov.ar/notas.asp?idCanal=0&id=22812 # confirms what Alex Krivenyshev has earlier sent to the tz # emailing list about that San Luis plans to return to standard # time much earlier than the rest of the country. It also # confirms that upon request the provinces San Juan and Mendoza # refused to follow San Luis in this change. # # The change is supposed to take place Monday the 21st at 0:00 # hours. As far as I understand it if this goes ahead, we need # a new timezone for San Luis (although there are also documented # independent changes in the southamerica file of San Luis in # 1990 and 1991 which has not been confirmed). # From Jesper Nørgaard Welen (2008-01-25): # Unfortunately the below page has become defunct, about the San Luis # time change. Perhaps because it now is part of a group of pages "Most # important pages of 2008." # # You can use # http://www.sanluis.gov.ar/notas.asp?idCanal=8141&id=22834 # instead it seems. Or use "Buscador" from the main page of the San Luis # government, and fill in "huso" and click OK, and you will get 3 pages # from which the first one is identical to the above. # From Mariano Absatz (2008-01-28): # I can confirm that the Province of San Luis (and so far only that # province) decided to go back to UTC-3 effective midnight Jan 20th 2008 # (that is, Monday 21st at 0:00 is the time the clocks were delayed back # 1 hour), and they intend to keep UTC-3 as their timezone all year round # (that is, unless they change their mind any minute now). # # So we'll have to add yet another city to 'southamerica' (I think San # Luis city is the mos populated city in the Province, so it'd be # America/Argentina/San_Luis... of course I can't remember if San Luis's # history of particular changes goes along with Mendoza or San Juan :-( # (I only remember not being able to collect hard facts about San Luis # back in 2004, when these provinces changed to UTC-4 for a few days, I # mailed them personally and never got an answer). # From Paul Eggert (2014-08-12): # Unless otherwise specified, data entries are from Shanks & Pottenger through # 1992, from the IATA otherwise. As noted below, Shanks & Pottenger say that # America/Cordoba split into 6 subregions during 1991/1992, one of which # was America/San_Luis, but we haven't verified this yet so for now we'll # keep America/Cordoba a single region rather than splitting it into the # other 5 subregions. # From Mariano Absatz (2009-03-13): # Yesterday (with our usual 2-day notice) the Province of San Luis # decided that next Sunday instead of "staying" @utc-03:00 they will go # to utc-04:00 until the second Saturday in October... # # The press release is at # http://www.sanluis.gov.ar/SL/Paginas/NoticiaDetalle.asp?TemaId=1&InfoPrensaId=3102 # (I couldn't find the decree, but www.sanluis.gov.ar # is the official page for the Province Government.) # # There's also a note in only one of the major national papers ... # http://www.lanacion.com.ar/nota.asp?nota_id=1107912 # # The press release says [quick and dirty translation]: # ... announced that next Sunday, at 00:00, Puntanos (the San Luis # inhabitants) will have to turn back one hour their clocks # # Since then, San Luis will establish its own Province timezone. Thus, # during 2009, this timezone change will run from 00:00 the third Sunday # in March until 24:00 of the second Saturday in October. # From Mariano Absatz (2009-10-16): # ...the Province of San Luis is a case in itself. # # The Law at # http://www.diputadossanluis.gov.ar/diputadosasp/paginas/verNorma.asp?NormaID=276 # is ambiguous because establishes a calendar from the 2nd Sunday in # October at 0:00 thru the 2nd Saturday in March at 24:00 and the # complement of that starting on the 2nd Sunday of March at 0:00 and # ending on the 2nd Saturday of March at 24:00. # # This clearly breaks every time the 1st of March or October is a Sunday. # # IMHO, the "spirit of the Law" is to make the changes at 0:00 on the 2nd # Sunday of October and March. # # The problem is that the changes in the rest of the Provinces that did # change in 2007/2008, were made according to the Federal Law and Decrees # that did so on the 3rd Sunday of October and March. # # In fact, San Luis actually switched from UTC-4 to UTC-3 last Sunday # (October 11th) at 0:00. # # So I guess a new set of rules, besides "Arg", must be made and the last # America/Argentina/San_Luis entries should change to use these... # ... # From Alexander Krivenyshev (2010-04-09): # According to news reports from El Diario de la República Province San # Luis, Argentina (standard time UTC-04) will keep Daylight Saving Time # after April 11, 2010 - will continue to have same time as rest of # Argentina (UTC-3) (no DST). # # Confirmaron la prórroga del huso horario de verano (Spanish) # http://www.eldiariodelarepublica.com/index.php?option=com_content&task=view&id=29383&Itemid=9 # or (some English translation): # http://www.worldtimezone.com/dst_news/dst_news_argentina08.html # From Mariano Absatz (2010-04-12): # yes...I can confirm this...and given that San Luis keeps calling # UTC-03:00 "summer time", we should't just let San Luis go back to "Arg" # rules...San Luis is still using "Western ARgentina Time" and it got # stuck on Summer daylight savings time even though the summer is over. # From Paul Eggert (2018-01-23): # Perhaps San Luis operates on the legal fiction that it is at -04 # with perpetual daylight saving time, but ordinary usage typically seems to # just say it's at -03; see, for example, # https://es.wikipedia.org/wiki/Hora_oficial_argentina # We've documented similar situations as being plain changes to # standard time, so let's do that here too. This does not change UTC # offsets, only tm_isdst and the time zone abbreviations. One minor # plus is that this silences a zic complaint that there's no POSIX TZ # setting for timestamps past 2038. # Zone NAME STDOFF RULES FORMAT [UNTIL] # # Buenos Aires (BA), Capital Federal (CF), Zone America/Argentina/Buenos_Aires -3:53:48 - LMT 1894 Oct 31 -4:16:48 - CMT 1920 May # Córdoba Mean Time -4:00 - -04 1930 Dec -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1999 Oct 3 -4:00 Arg -04/-03 2000 Mar 3 -3:00 Arg -03/-02 # # Córdoba (CB), Santa Fe (SF), Entre Ríos (ER), Corrientes (CN), Misiones (MN), # Chaco (CC), Formosa (FM), Santiago del Estero (SE) # # Shanks & Pottenger also make the following claims, which we haven't verified: # - Formosa switched to -3:00 on 1991-01-07. # - Misiones switched to -3:00 on 1990-12-29. # - Chaco switched to -3:00 on 1991-01-04. # - Santiago del Estero switched to -4:00 on 1991-04-01, # then to -3:00 on 1991-04-26. # Zone America/Argentina/Cordoba -4:16:48 - LMT 1894 Oct 31 -4:16:48 - CMT 1920 May -4:00 - -04 1930 Dec -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1991 Mar 3 -4:00 - -04 1991 Oct 20 -3:00 Arg -03/-02 1999 Oct 3 -4:00 Arg -04/-03 2000 Mar 3 -3:00 Arg -03/-02 # # Salta (SA), La Pampa (LP), Neuquén (NQ), Rio Negro (RN) Zone America/Argentina/Salta -4:21:40 - LMT 1894 Oct 31 -4:16:48 - CMT 1920 May -4:00 - -04 1930 Dec -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1991 Mar 3 -4:00 - -04 1991 Oct 20 -3:00 Arg -03/-02 1999 Oct 3 -4:00 Arg -04/-03 2000 Mar 3 -3:00 Arg -03/-02 2008 Oct 18 -3:00 - -03 # # Tucumán (TM) Zone America/Argentina/Tucuman -4:20:52 - LMT 1894 Oct 31 -4:16:48 - CMT 1920 May -4:00 - -04 1930 Dec -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1991 Mar 3 -4:00 - -04 1991 Oct 20 -3:00 Arg -03/-02 1999 Oct 3 -4:00 Arg -04/-03 2000 Mar 3 -3:00 - -03 2004 Jun 1 -4:00 - -04 2004 Jun 13 -3:00 Arg -03/-02 # # La Rioja (LR) Zone America/Argentina/La_Rioja -4:27:24 - LMT 1894 Oct 31 -4:16:48 - CMT 1920 May -4:00 - -04 1930 Dec -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1991 Mar 1 -4:00 - -04 1991 May 7 -3:00 Arg -03/-02 1999 Oct 3 -4:00 Arg -04/-03 2000 Mar 3 -3:00 - -03 2004 Jun 1 -4:00 - -04 2004 Jun 20 -3:00 Arg -03/-02 2008 Oct 18 -3:00 - -03 # # San Juan (SJ) Zone America/Argentina/San_Juan -4:34:04 - LMT 1894 Oct 31 -4:16:48 - CMT 1920 May -4:00 - -04 1930 Dec -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1991 Mar 1 -4:00 - -04 1991 May 7 -3:00 Arg -03/-02 1999 Oct 3 -4:00 Arg -04/-03 2000 Mar 3 -3:00 - -03 2004 May 31 -4:00 - -04 2004 Jul 25 -3:00 Arg -03/-02 2008 Oct 18 -3:00 - -03 # # Jujuy (JY) Zone America/Argentina/Jujuy -4:21:12 - LMT 1894 Oct 31 -4:16:48 - CMT 1920 May -4:00 - -04 1930 Dec -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1990 Mar 4 -4:00 - -04 1990 Oct 28 -4:00 1:00 -03 1991 Mar 17 -4:00 - -04 1991 Oct 6 -3:00 1:00 -02 1992 -3:00 Arg -03/-02 1999 Oct 3 -4:00 Arg -04/-03 2000 Mar 3 -3:00 Arg -03/-02 2008 Oct 18 -3:00 - -03 # # Catamarca (CT), Chubut (CH) Zone America/Argentina/Catamarca -4:23:08 - LMT 1894 Oct 31 -4:16:48 - CMT 1920 May -4:00 - -04 1930 Dec -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1991 Mar 3 -4:00 - -04 1991 Oct 20 -3:00 Arg -03/-02 1999 Oct 3 -4:00 Arg -04/-03 2000 Mar 3 -3:00 - -03 2004 Jun 1 -4:00 - -04 2004 Jun 20 -3:00 Arg -03/-02 2008 Oct 18 -3:00 - -03 # # Mendoza (MZ) Zone America/Argentina/Mendoza -4:35:16 - LMT 1894 Oct 31 -4:16:48 - CMT 1920 May -4:00 - -04 1930 Dec -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1990 Mar 4 -4:00 - -04 1990 Oct 15 -4:00 1:00 -03 1991 Mar 1 -4:00 - -04 1991 Oct 15 -4:00 1:00 -03 1992 Mar 1 -4:00 - -04 1992 Oct 18 -3:00 Arg -03/-02 1999 Oct 3 -4:00 Arg -04/-03 2000 Mar 3 -3:00 - -03 2004 May 23 -4:00 - -04 2004 Sep 26 -3:00 Arg -03/-02 2008 Oct 18 -3:00 - -03 # # San Luis (SL) Rule SanLuis 2008 2009 - Mar Sun>=8 0:00 0 - Rule SanLuis 2007 2008 - Oct Sun>=8 0:00 1:00 - Zone America/Argentina/San_Luis -4:25:24 - LMT 1894 Oct 31 -4:16:48 - CMT 1920 May -4:00 - -04 1930 Dec -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1990 -3:00 1:00 -02 1990 Mar 14 -4:00 - -04 1990 Oct 15 -4:00 1:00 -03 1991 Mar 1 -4:00 - -04 1991 Jun 1 -3:00 - -03 1999 Oct 3 -4:00 1:00 -03 2000 Mar 3 -3:00 - -03 2004 May 31 -4:00 - -04 2004 Jul 25 -3:00 Arg -03/-02 2008 Jan 21 -4:00 SanLuis -04/-03 2009 Oct 11 -3:00 - -03 # # Santa Cruz (SC) Zone America/Argentina/Rio_Gallegos -4:36:52 - LMT 1894 Oct 31 -4:16:48 - CMT 1920 May -4:00 - -04 1930 Dec -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1999 Oct 3 -4:00 Arg -04/-03 2000 Mar 3 -3:00 - -03 2004 Jun 1 -4:00 - -04 2004 Jun 20 -3:00 Arg -03/-02 2008 Oct 18 -3:00 - -03 # # Tierra del Fuego, Antártida e Islas del Atlántico Sur (TF) Zone America/Argentina/Ushuaia -4:33:12 - LMT 1894 Oct 31 -4:16:48 - CMT 1920 May -4:00 - -04 1930 Dec -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1999 Oct 3 -4:00 Arg -04/-03 2000 Mar 3 -3:00 - -03 2004 May 30 -4:00 - -04 2004 Jun 20 -3:00 Arg -03/-02 2008 Oct 18 -3:00 - -03 # Aruba # See America/Puerto_Rico. # Bolivia # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/La_Paz -4:32:36 - LMT 1890 -4:32:36 - CMT 1931 Oct 15 # Calamarca MT -4:32:36 1:00 BST 1932 Mar 21 # Bolivia ST -4:00 - -04 # Brazil # From Paul Eggert (1993-11-18): # The mayor of Rio recently attempted to change the time zone rules # just in his city, in order to leave more summer time for the tourist trade. # The rule change lasted only part of the day; # the federal government refused to follow the city's rules, and business # was in a chaos, so the mayor backed down that afternoon. # From IATA SSIM (1996-02): # _Only_ the following states in BR1 observe DST: Rio Grande do Sul (RS), # Santa Catarina (SC), Paraná (PR), São Paulo (SP), Rio de Janeiro (RJ), # Espírito Santo (ES), Minas Gerais (MG), Bahia (BA), Goiás (GO), # Distrito Federal (DF), Tocantins (TO), Sergipe [SE] and Alagoas [AL]. # [The last three states are new to this issue of the IATA SSIM.] # From Gwillim Law (1996-10-07): # Geography, history (Tocantins was part of Goiás until 1989), and other # sources of time zone information lead me to believe that AL, SE, and TO were # always in BR1, and so the only change was whether or not they observed DST.... # The earliest issue of the SSIM I have is 2/91. Each issue from then until # 9/95 says that DST is observed only in the ten states I quoted from 9/95, # along with Mato Grosso (MT) and Mato Grosso do Sul (MS), which are in BR2 # (UTC-4).... The other two time zones given for Brazil are BR3, which is # UTC-5, no DST, and applies only in the state of Acre (AC); and BR4, which is # UTC-2, and applies to Fernando de Noronha (formerly FN, but I believe it's # become part of the state of Pernambuco). The boundary between BR1 and BR2 # has never been clearly stated. They've simply been called East and West. # However, some conclusions can be drawn from another IATA manual: the Airline # Coding Directory, which lists close to 400 airports in Brazil. For each # airport it gives a time zone which is coded to the SSIM. From that # information, I'm led to conclude that the states of Amapá (AP), Ceará (CE), # Maranhão (MA), Paraíba (PR), Pernambuco (PE), Piauí (PI), and Rio Grande do # Norte (RN), and the eastern part of Pará (PA) are all in BR1 without DST. # From Marcos Tadeu (1998-09-27): # Brazilian official page # From Jesper Nørgaard (2000-11-03): # [For an official list of which regions in Brazil use which time zones, see:] # http://pcdsh01.on.br/Fusbr.htm # http://pcdsh01.on.br/Fusbrhv.htm # From Celso Doria via David Madeo (2002-10-09): # The reason for the delay this year has to do with elections in Brazil. # # Unlike in the United States, elections in Brazil are 100% computerized and # the results are known almost immediately. Yesterday, it was the first # round of the elections when 115 million Brazilians voted for President, # Governor, Senators, Federal Deputies, and State Deputies. Nobody is # counting (or re-counting) votes anymore and we know there will be a second # round for the Presidency and also for some Governors. The 2nd round will # take place on October 27th. # # The reason why the DST will only begin November 3rd is that the thousands # of electoral machines used cannot have their time changed, and since the # Constitution says the elections must begin at 8:00 AM and end at 5:00 PM, # the Government decided to postpone DST, instead of changing the Constitution # (maybe, for the next elections, it will be possible to change the clock)... # From Rodrigo Severo (2004-10-04): # It's just the biannual change made necessary by the much hyped, supposedly # modern Brazilian eletronic voting machines which, apparently, can't deal # with a time change between the first and the second rounds of the elections. # From Steffen Thorsen (2007-09-20): # Brazil will start DST on 2007-10-14 00:00 and end on 2008-02-17 00:00: # http://www.mme.gov.br/site/news/detail.do;jsessionid=BBA06811AFCAAC28F0285210913513DA?newsId=13975 # From Paul Schulze (2008-06-24): # ...by law number 11.662 of April 24, 2008 (published in the "Diario # Oficial da União"...) in Brazil there are changes in the timezones, # effective today (00:00am at June 24, 2008) as follows: # # a) The timezone UTC+5 is extinguished, with all the Acre state and the # part of the Amazonas state that had this timezone now being put to the # timezone UTC+4 # b) The whole Pará state now is put at timezone UTC+3, instead of just # part of it, as was before. # # This change follows a proposal of senator Tiao Viana of Acre state, that # proposed it due to concerns about open television channels displaying # programs inappropriate to youths in the states that had the timezone # UTC+5 too early in the night. In the occasion, some more corrections # were proposed, trying to unify the timezones of any given state. This # change modifies timezone rules defined in decree 2.784 of 18 June, # 1913. # From Rodrigo Severo (2008-06-24): # Just correcting the URL: # https://www.in.gov.br/imprensa/visualiza/index.jsp?jornal=do&secao=1&pagina=1&data=25/04/2008 # # As a result of the above Decree I believe the America/Rio_Branco # timezone shall be modified from UTC-5 to UTC-4 and a new timezone shall # be created to represent the...west side of the Pará State. I # suggest this new timezone be called Santarem as the most # important/populated city in the affected area. # # This new timezone would be the same as the Rio_Branco timezone up to # the 2008/06/24 change which would be to UTC-3 instead of UTC-4. # From Alex Krivenyshev (2008-06-24): # This is a quick reference page for New and Old Brazil Time Zones map. # http://www.worldtimezone.com/brazil-time-new-old.php # # - 4 time zones replaced by 3 time zones - eliminating time zone UTC-05 # (state Acre and the part of the Amazonas will be UTC/GMT-04) - western # part of Par state is moving to one timezone UTC-03 (from UTC-04). # From Paul Eggert (2002-10-10): # The official decrees referenced below are mostly taken from # Decretos sobre o Horário de Verão no Brasil. # http://pcdsh01.on.br/DecHV.html # From Steffen Thorsen (2008-08-29): # As announced by the government and many newspapers in Brazil late # yesterday, Brazil will start DST on 2008-10-19 (need to change rule) and # it will end on 2009-02-15 (current rule for Brazil is fine). Based on # past years experience with the elections, there was a good chance that # the start was postponed to November, but it did not happen this year. # # It has not yet been posted to http://pcdsh01.on.br/DecHV.html # # An official page about it: # http://www.mme.gov.br/site/news/detail.do?newsId=16722 # Note that this link does not always work directly, but must be accessed # by going to # http://www.mme.gov.br/first # # One example link that works directly: # http://jornale.com.br/index.php?option=com_content&task=view&id=13530&Itemid=54 # (Portuguese) # # We have a written a short article about it as well: # https://www.timeanddate.com/news/time/brazil-dst-2008-2009.html # # From Alexander Krivenyshev (2011-10-04): # State Bahia will return to Daylight savings time this year after 8 years off. # The announcement was made by Governor Jaques Wagner in an interview to a # television station in Salvador. # In Portuguese: # http://g1.globo.com/bahia/noticia/2011/10/governador-jaques-wagner-confirma-horario-de-verao-na-bahia.html # https://noticias.terra.com.br/brasil/noticias/0,,OI5390887-EI8139,00-Bahia+volta+a+ter+horario+de+verao+apos+oito+anos.html # From Guilherme Bernardes Rodrigues (2011-10-07): # There is news in the media, however there is still no decree about it. # I just send a e-mail to Zulmira Brandao at http://pcdsh01.on.br/ the # official agency about time in Brazil, and she confirmed that the old rule is # still in force. # From Guilherme Bernardes Rodrigues (2011-10-14) # It's official, the President signed a decree that includes Bahia in summer # time. # [ and in a second message (same day): ] # I found the decree. # # DECRETO No. 7.584, DE 13 DE OUTUBRO DE 2011 # Link : # http://www.in.gov.br/visualiza/index.jsp?data=13/10/2011&jornal=1000&pagina=6&totalArquivos=6 # From Kelley Cook (2012-10-16): # The governor of state of Bahia in Brazil announced on Thursday that # due to public pressure, he is reversing the DST policy they implemented # last year and will not be going to Summer Time on October 21st.... # http://www.correio24horas.com.br/r/artigo/apos-pressoes-wagner-suspende-horario-de-verao-na-bahia # From Rodrigo Severo (2012-10-16): # Tocantins state will have DST. # https://noticias.terra.com.br/brasil/noticias/0,,OI6232536-EI306.html # From Steffen Thorsen (2013-09-20): # Tocantins in Brazil is very likely not to observe DST from October.... # http://conexaoto.com.br/2013/09/18/ministerio-confirma-que-tocantins-esta-fora-do-horario-de-verao-em-2013-mas-falta-publicacao-de-decreto # We will keep this article updated when this is confirmed: # https://www.timeanddate.com/news/time/brazil-starts-dst-2013.html # From Steffen Thorsen (2013-10-17): # https://www.timeanddate.com/news/time/acre-amazonas-change-time-zone.html # Senator Jorge Viana announced that Acre will change time zone on November 10. # He did not specify the time of the change, nor if western parts of Amazonas # will change as well. # # From Paul Eggert (2013-10-17): # For now, assume western Amazonas will change as well. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S # Decree 20,466 (1931-10-01) # Decree 21,896 (1932-01-10) Rule Brazil 1931 only - Oct 3 11:00 1:00 - Rule Brazil 1932 1933 - Apr 1 0:00 0 - Rule Brazil 1932 only - Oct 3 0:00 1:00 - # Decree 23,195 (1933-10-10) # revoked DST. # Decree 27,496 (1949-11-24) # Decree 27,998 (1950-04-13) Rule Brazil 1949 1952 - Dec 1 0:00 1:00 - Rule Brazil 1950 only - Apr 16 1:00 0 - Rule Brazil 1951 1952 - Apr 1 0:00 0 - # Decree 32,308 (1953-02-24) Rule Brazil 1953 only - Mar 1 0:00 0 - # Decree 34,724 (1953-11-30) # revoked DST. # Decree 52,700 (1963-10-18) # established DST from 1963-10-23 00:00 to 1964-02-29 00:00 # in SP, RJ, GB, MG, ES, due to the prolongation of the drought. # Decree 53,071 (1963-12-03) # extended the above decree to all of the national territory on 12-09. Rule Brazil 1963 only - Dec 9 0:00 1:00 - # Decree 53,604 (1964-02-25) # extended summer time by one day to 1964-03-01 00:00 (start of school). Rule Brazil 1964 only - Mar 1 0:00 0 - # Decree 55,639 (1965-01-27) Rule Brazil 1965 only - Jan 31 0:00 1:00 - Rule Brazil 1965 only - Mar 31 0:00 0 - # Decree 57,303 (1965-11-22) Rule Brazil 1965 only - Dec 1 0:00 1:00 - # Decree 57,843 (1966-02-18) Rule Brazil 1966 1968 - Mar 1 0:00 0 - Rule Brazil 1966 1967 - Nov 1 0:00 1:00 - # Decree 63,429 (1968-10-15) # revoked DST. # Decree 91,698 (1985-09-27) Rule Brazil 1985 only - Nov 2 0:00 1:00 - # Decree 92,310 (1986-01-21) # Decree 92,463 (1986-03-13) Rule Brazil 1986 only - Mar 15 0:00 0 - # Decree 93,316 (1986-10-01) Rule Brazil 1986 only - Oct 25 0:00 1:00 - Rule Brazil 1987 only - Feb 14 0:00 0 - # Decree 94,922 (1987-09-22) Rule Brazil 1987 only - Oct 25 0:00 1:00 - Rule Brazil 1988 only - Feb 7 0:00 0 - # Decree 96,676 (1988-09-12) # except for the states of AC, AM, PA, RR, RO, and AP (then a territory) Rule Brazil 1988 only - Oct 16 0:00 1:00 - Rule Brazil 1989 only - Jan 29 0:00 0 - # Decree 98,077 (1989-08-21) # with the same exceptions Rule Brazil 1989 only - Oct 15 0:00 1:00 - Rule Brazil 1990 only - Feb 11 0:00 0 - # Decree 99,530 (1990-09-17) # adopted by RS, SC, PR, SP, RJ, ES, MG, GO, MS, DF. # Decree 99,629 (1990-10-19) adds BA, MT. Rule Brazil 1990 only - Oct 21 0:00 1:00 - Rule Brazil 1991 only - Feb 17 0:00 0 - # Unnumbered decree (1991-09-25) # adopted by RS, SC, PR, SP, RJ, ES, MG, BA, GO, MT, MS, DF. Rule Brazil 1991 only - Oct 20 0:00 1:00 - Rule Brazil 1992 only - Feb 9 0:00 0 - # Unnumbered decree (1992-10-16) # adopted by same states. Rule Brazil 1992 only - Oct 25 0:00 1:00 - Rule Brazil 1993 only - Jan 31 0:00 0 - # Decree 942 (1993-09-28) # adopted by same states, plus AM. # Decree 1,252 (1994-09-22; # web page corrected 2004-01-07) adopted by same states, minus AM. # Decree 1,636 (1995-09-14) # adopted by same states, plus MT and TO. # Decree 1,674 (1995-10-13) # adds AL, SE. Rule Brazil 1993 1995 - Oct Sun>=11 0:00 1:00 - Rule Brazil 1994 1995 - Feb Sun>=15 0:00 0 - Rule Brazil 1996 only - Feb 11 0:00 0 - # Decree 2,000 (1996-09-04) # adopted by same states, minus AL, SE. Rule Brazil 1996 only - Oct 6 0:00 1:00 - Rule Brazil 1997 only - Feb 16 0:00 0 - # From Daniel C. Sobral (1998-02-12): # In 1997, the DS began on October 6. The stated reason was that # because international television networks ignored Brazil's policy on DS, # they bought the wrong times on satellite for coverage of Pope's visit. # This year, the ending date of DS was postponed to March 1 # to help dealing with the shortages of electric power. # # Decree 2,317 (1997-09-04), adopted by same states. Rule Brazil 1997 only - Oct 6 0:00 1:00 - # Decree 2,495 # (1998-02-10) Rule Brazil 1998 only - Mar 1 0:00 0 - # Decree 2,780 (1998-09-11) # adopted by the same states as before. Rule Brazil 1998 only - Oct 11 0:00 1:00 - Rule Brazil 1999 only - Feb 21 0:00 0 - # Decree 3,150 # (1999-08-23) adopted by same states. # Decree 3,188 (1999-09-30) # adds SE, AL, PB, PE, RN, CE, PI, MA and RR. Rule Brazil 1999 only - Oct 3 0:00 1:00 - Rule Brazil 2000 only - Feb 27 0:00 0 - # Decree 3,592 (2000-09-06) # adopted by the same states as before. # Decree 3,630 (2000-10-13) # repeals DST in PE and RR, effective 2000-10-15 00:00. # Decree 3,632 (2000-10-17) # repeals DST in SE, AL, PB, RN, CE, PI and MA, effective 2000-10-22 00:00. # Decree 3,916 # (2001-09-13) reestablishes DST in AL, CE, MA, PB, PE, PI, RN, SE. Rule Brazil 2000 2001 - Oct Sun>=8 0:00 1:00 - Rule Brazil 2001 2006 - Feb Sun>=15 0:00 0 - # Decree 4,399 (2002-10-01) repeals DST in AL, CE, MA, PB, PE, PI, RN, SE. # 4,399 Rule Brazil 2002 only - Nov 3 0:00 1:00 - # Decree 4,844 (2003-09-24; corrected 2003-09-26) repeals DST in BA, MT, TO. # 4,844 Rule Brazil 2003 only - Oct 19 0:00 1:00 - # Decree 5,223 (2004-10-01) reestablishes DST in MT. # 5,223 Rule Brazil 2004 only - Nov 2 0:00 1:00 - # Decree 5,539 (2005-09-19), # adopted by the same states as before. Rule Brazil 2005 only - Oct 16 0:00 1:00 - # Decree 5,920 (2006-10-03), # adopted by the same states as before. Rule Brazil 2006 only - Nov 5 0:00 1:00 - Rule Brazil 2007 only - Feb 25 0:00 0 - # Decree 6,212 (2007-09-26), # adopted by the same states as before. Rule Brazil 2007 only - Oct Sun>=8 0:00 1:00 - # From Frederico A. C. Neves (2008-09-10): # According to this decree # http://www.planalto.gov.br/ccivil_03/_Ato2007-2010/2008/Decreto/D6558.htm # [t]he DST period in Brazil now on will be from the 3rd Oct Sunday to the # 3rd Feb Sunday. There is an exception on the return date when this is # the Carnival Sunday then the return date will be the next Sunday... Rule Brazil 2008 2017 - Oct Sun>=15 0:00 1:00 - Rule Brazil 2008 2011 - Feb Sun>=15 0:00 0 - # Decree 7,584 (2011-10-13) # added Bahia. Rule Brazil 2012 only - Feb Sun>=22 0:00 0 - # Decree 7,826 (2012-10-15) # removed Bahia and added Tocantins. # Decree 8,112 (2013-09-30) # removed Tocantins. Rule Brazil 2013 2014 - Feb Sun>=15 0:00 0 - Rule Brazil 2015 only - Feb Sun>=22 0:00 0 - Rule Brazil 2016 2019 - Feb Sun>=15 0:00 0 - # From Steffen Thorsen (2017-12-18): # According to many media sources, next year's DST start in Brazil will move to # the first Sunday of November # ... https://www.timeanddate.com/news/time/brazil-delays-dst-2018.html # From Steffen Thorsen (2017-12-20): # http://www.planalto.gov.br/ccivil_03/_ato2015-2018/2017/decreto/D9242.htm # From Fábio Gomes (2018-10-04): # The Brazilian president just announced a new change on this year DST. # It was scheduled to start on November 4th and it was changed to November 18th. # From Rodrigo Brüning Wessler (2018-10-15): # The Brazilian government just announced that the change in DST was # canceled.... Maybe the president Michel Temer also woke up one hour # earlier today. :) Rule Brazil 2018 only - Nov Sun>=1 0:00 1:00 - # The last ruleset listed above says that the following states observed DST: # DF, ES, GO, MG, MS, MT, PR, RJ, RS, SC, SP. # # From Steffen Thorsen (2019-04-05): # According to multiple sources the Brazilian president wants to get rid of DST. # https://gmconline.com.br/noticias/politica/bolsonaro-horario-de-verao-deve-acabar-este-ano # https://g1.globo.com/economia/noticia/2019/04/05/governo-anuncia-fim-do-horario-de-verao.ghtml # From Marcus Diniz (2019-04-25): # Brazil no longer has DST changes - decree signed today # https://g1.globo.com/politica/noticia/2019/04/25/bolsonaro-assina-decreto-que-acaba-com-o-horario-de-verao.ghtml # From Daniel Soares de Oliveira (2019-04-26): # http://www.planalto.gov.br/ccivil_03/_Ato2019-2022/2019/Decreto/D9772.htm # Zone NAME STDOFF RULES FORMAT [UNTIL] # # Fernando de Noronha (administratively part of PE) Zone America/Noronha -2:09:40 - LMT 1914 -2:00 Brazil -02/-01 1990 Sep 17 -2:00 - -02 1999 Sep 30 -2:00 Brazil -02/-01 2000 Oct 15 -2:00 - -02 2001 Sep 13 -2:00 Brazil -02/-01 2002 Oct 1 -2:00 - -02 # Other Atlantic islands have no permanent settlement. # These include Trindade and Martim Vaz (administratively part of ES), # Rocas Atoll (RN), and the St Peter and St Paul Archipelago (PE). # Fernando de Noronha was a separate territory from 1942-09-02 to 1989-01-01; # it also included the Penedos. # # Amapá (AP), east Pará (PA) # East Pará includes Belém, Marabá, Serra Norte, and São Félix do Xingu. # The division between east and west Pará is the river Xingu. # In the north a very small part from the river Javary (now Jari I guess, # the border with Amapá) to the Amazon, then to the Xingu. Zone America/Belem -3:13:56 - LMT 1914 -3:00 Brazil -03/-02 1988 Sep 12 -3:00 - -03 # # west Pará (PA) # West Pará includes Altamira, Óbidos, Prainha, Oriximiná, and Santarém. Zone America/Santarem -3:38:48 - LMT 1914 -4:00 Brazil -04/-03 1988 Sep 12 -4:00 - -04 2008 Jun 24 0:00 -3:00 - -03 # # Maranhão (MA), Piauí (PI), Ceará (CE), Rio Grande do Norte (RN), # Paraíba (PB) Zone America/Fortaleza -2:34:00 - LMT 1914 -3:00 Brazil -03/-02 1990 Sep 17 -3:00 - -03 1999 Sep 30 -3:00 Brazil -03/-02 2000 Oct 22 -3:00 - -03 2001 Sep 13 -3:00 Brazil -03/-02 2002 Oct 1 -3:00 - -03 # # Pernambuco (PE) (except Atlantic islands) Zone America/Recife -2:19:36 - LMT 1914 -3:00 Brazil -03/-02 1990 Sep 17 -3:00 - -03 1999 Sep 30 -3:00 Brazil -03/-02 2000 Oct 15 -3:00 - -03 2001 Sep 13 -3:00 Brazil -03/-02 2002 Oct 1 -3:00 - -03 # # Tocantins (TO) Zone America/Araguaina -3:12:48 - LMT 1914 -3:00 Brazil -03/-02 1990 Sep 17 -3:00 - -03 1995 Sep 14 -3:00 Brazil -03/-02 2003 Sep 24 -3:00 - -03 2012 Oct 21 -3:00 Brazil -03/-02 2013 Sep -3:00 - -03 # # Alagoas (AL), Sergipe (SE) Zone America/Maceio -2:22:52 - LMT 1914 -3:00 Brazil -03/-02 1990 Sep 17 -3:00 - -03 1995 Oct 13 -3:00 Brazil -03/-02 1996 Sep 4 -3:00 - -03 1999 Sep 30 -3:00 Brazil -03/-02 2000 Oct 22 -3:00 - -03 2001 Sep 13 -3:00 Brazil -03/-02 2002 Oct 1 -3:00 - -03 # # Bahia (BA) # There are too many Salvadors elsewhere, so use America/Bahia instead # of America/Salvador. Zone America/Bahia -2:34:04 - LMT 1914 -3:00 Brazil -03/-02 2003 Sep 24 -3:00 - -03 2011 Oct 16 -3:00 Brazil -03/-02 2012 Oct 21 -3:00 - -03 # # Goiás (GO), Distrito Federal (DF), Minas Gerais (MG), # Espírito Santo (ES), Rio de Janeiro (RJ), São Paulo (SP), Paraná (PR), # Santa Catarina (SC), Rio Grande do Sul (RS) Zone America/Sao_Paulo -3:06:28 - LMT 1914 -3:00 Brazil -03/-02 1963 Oct 23 0:00 -3:00 1:00 -02 1964 -3:00 Brazil -03/-02 # # Mato Grosso do Sul (MS) Zone America/Campo_Grande -3:38:28 - LMT 1914 -4:00 Brazil -04/-03 # # Mato Grosso (MT) Zone America/Cuiaba -3:44:20 - LMT 1914 -4:00 Brazil -04/-03 2003 Sep 24 -4:00 - -04 2004 Oct 1 -4:00 Brazil -04/-03 # # Rondônia (RO) Zone America/Porto_Velho -4:15:36 - LMT 1914 -4:00 Brazil -04/-03 1988 Sep 12 -4:00 - -04 # # Roraima (RR) Zone America/Boa_Vista -4:02:40 - LMT 1914 -4:00 Brazil -04/-03 1988 Sep 12 -4:00 - -04 1999 Sep 30 -4:00 Brazil -04/-03 2000 Oct 15 -4:00 - -04 # # east Amazonas (AM): Boca do Acre, Jutaí, Manaus, Floriano Peixoto # The great circle line from Tabatinga to Porto Acre divides # east from west Amazonas. Zone America/Manaus -4:00:04 - LMT 1914 -4:00 Brazil -04/-03 1988 Sep 12 -4:00 - -04 1993 Sep 28 -4:00 Brazil -04/-03 1994 Sep 22 -4:00 - -04 # # west Amazonas (AM): Atalaia do Norte, Boca do Maoco, Benjamin Constant, # Eirunepé, Envira, Ipixuna Zone America/Eirunepe -4:39:28 - LMT 1914 -5:00 Brazil -05/-04 1988 Sep 12 -5:00 - -05 1993 Sep 28 -5:00 Brazil -05/-04 1994 Sep 22 -5:00 - -05 2008 Jun 24 0:00 -4:00 - -04 2013 Nov 10 -5:00 - -05 # # Acre (AC) Zone America/Rio_Branco -4:31:12 - LMT 1914 -5:00 Brazil -05/-04 1988 Sep 12 -5:00 - -05 2008 Jun 24 0:00 -4:00 - -04 2013 Nov 10 -5:00 - -05 # Chile # From Paul Eggert (2015-04-03): # Shanks & Pottenger says America/Santiago introduced standard time in # 1890 and rounds its UT offset to 70W40; guess that in practice this # was the same offset as in 1916-1919. It also says Pacific/Easter # standardized on 109W22 in 1890; assume this didn't change the clocks. # # Dates for America/Santiago from 1910 to 2004 are primarily from # the following source, cited by Oscar van Vlijmen (2006-10-08): # [1] Chile Law # http://www.webexhibits.org/daylightsaving/chile.html # This contains a copy of this official table: # Cambios en la hora oficial de Chile desde 1900 (retrieved 2008-03-30) # https://web.archive.org/web/20080330200901/http://www.horaoficial.cl/cambio.htm # [1] needs several corrections, though. # # The first set of corrections is from: # [2] History of the Official Time of Chile # http://www.horaoficial.cl/ing/horaof_ing.html (retrieved 2012-03-06). See: # https://web.archive.org/web/20120306042032/http://www.horaoficial.cl/ing/horaof_ing.html # This is an English translation of: # Historia de la hora oficial de Chile (retrieved 2012-10-24). See: # https://web.archive.org/web/20121024234627/http://www.horaoficial.cl/horaof.htm # A fancier Spanish version (requiring mouse-clicking) is at: # http://www.horaoficial.cl/historia_hora.html # Conflicts between [1] and [2] were resolved as follows: # # - [1] says the 1910 transition was Jan 1, [2] says Jan 10 and cites # Boletín No. 1, Aviso No. 1 (1910). Go with [2]. # # - [1] says SMT was -4:42:45, [2] says Chile's official time from # 1916 to 1919 was -4:42:46.3, the meridian of Chile's National # Astronomical Observatory (OAN), then located in what is now # Quinta Normal in Santiago. Go with [2], rounding it to -4:42:46. # # - [1] says the 1918 transition was Sep 1, [2] says Sep 10 and cites # Boletín No. 22, Aviso No. 129/1918 (1918-08-23). Go with [2]. # # - [1] does not give times for transitions; assume they occur # at midnight mainland time, the current common practice. However, # go with [2]'s specification of 23:00 for the 1947-05-21 transition. # # Another correction to [1] is from Jesper Nørgaard Welen, who # wrote (2006-10-08), "I think that there are some obvious mistakes in # the suggested link from Oscar van Vlijmen,... for instance entry 66 # says that GMT-4 ended 1990-09-12 while entry 67 only begins GMT-3 at # 1990-09-15 (they should have been 1990-09-15 and 1990-09-16 # respectively), but anyhow it clears up some doubts too." # # Data for Pacific/Easter from 1910 through 1967 come from Shanks & # Pottenger. After that, for lack of better info assume # Pacific/Easter is always two hours behind America/Santiago; # this is known to work for DST transitions starting in 2008 and # may well be true for earlier transitions. # From Eduardo Krell (1995-10-19): # The law says to switch to DST at midnight [24:00] on the second SATURDAY # of October.... The law is the same for March and October. # (1998-09-29): # Because of the drought this year, the government decided to go into # DST earlier (saturday 9/26 at 24:00). This is a one-time change only ... # (unless there's another dry season next year, I guess). # From Julio I. Pacheco Troncoso (1999-03-18): # Because of the same drought, the government decided to end DST later, # on April 3, (one-time change). # From Germán Poo-Caamaño (2008-03-03): # Due to drought, Chile extends Daylight Time in three weeks. This # is one-time change (Saturday 3/29 at 24:00 for America/Santiago # and Saturday 3/29 at 22:00 for Pacific/Easter) # The Supreme Decree is located at # http://www.shoa.cl/servicios/supremo316.pdf # # From José Miguel Garrido (2008-03-05): # http://www.shoa.cl/noticias/2008/04hora/hora.htm # From Angel Chiang (2010-03-04): # Subject: DST in Chile exceptionally extended to 3 April due to earthquake # http://www.gobiernodechile.cl/viewNoticia.aspx?idArticulo=30098 # # From Arthur David Olson (2010-03-06): # Angel Chiang's message confirmed by Julio Pacheco; Julio provided a patch. # From Glenn Eychaner (2011-03-28): # http://diario.elmercurio.com/2011/03/28/_portada/_portada/noticias/7565897A-CA86-49E6-9E03-660B21A4883E.htm?id=3D{7565897A-CA86-49E6-9E03-660B21A4883E} # In English: # Chile's clocks will go back an hour this year on the 7th of May instead # of this Saturday. They will go forward again the 3rd Saturday in # August, not in October as they have since 1968. # From Mauricio Parada (2012-02-22), translated by Glenn Eychaner (2012-02-23): # As stated in the website of the Chilean Energy Ministry # http://www.minenergia.cl/ministerio/noticias/generales/gobierno-anuncia-fechas-de-cambio-de.html # The Chilean Government has decided to postpone the entrance into winter time # (to leave DST) from March 11 2012 to April 28th 2012.... # Quote from the website communication: # # 6. For the year 2012, the dates of entry into winter time will be as follows: # a. Saturday April 28, 2012, clocks should go back 60 minutes; that is, at # 23:59:59, instead of passing to 0:00, the time should be adjusted to be 23:00 # of the same day. # b. Saturday, September 1, 2012, clocks should go forward 60 minutes; that is, # at 23:59:59, instead of passing to 0:00, the time should be adjusted to be # 01:00 on September 2. # From Steffen Thorsen (2013-02-15): # According to several news sources, Chile has extended DST this year, # they will end DST later and start DST earlier than planned. They # hope to save energy. The new end date is 2013-04-28 00:00 and new # start date is 2013-09-08 00:00.... # http://www.gob.cl/informa/2013/02/15/gobierno-anuncia-fechas-de-cambio-de-hora-para-el-ano-2013.htm # From José Miguel Garrido (2014-02-19): # Today appeared in the Diario Oficial a decree amending the time change # dates to 2014. # DST End: last Saturday of April 2014 (Sun 27 Apr 2014 03:00 UTC) # DST Start: first Saturday of September 2014 (Sun 07 Sep 2014 04:00 UTC) # http://www.diariooficial.interior.gob.cl//media/2014/02/19/do-20140219.pdf # From Eduardo Romero Urra (2015-03-03): # Today has been published officially that Chile will use the DST time # permanently until March 25 of 2017 # http://www.diariooficial.interior.gob.cl/media/2015/03/03/1-large.jpg # # From Paul Eggert (2015-03-03): # For now, assume that the extension will persist indefinitely. # From Juan Correa (2016-03-18): # The decree regarding DST has been published in today's Official Gazette: # http://www.diariooficial.interior.gob.cl/versiones-anteriores/do/20160318/ # http://www.leychile.cl/Navegar?idNorma=1088502 # It does consider the second Saturday of May and August as the dates # for the transition; and it lists DST dates until 2019, but I think # this scheme will stick. # # From Paul Eggert (2016-03-18): # For now, assume the pattern holds for the indefinite future. # The decree says transitions occur at 24:00; in practice this appears # to mean 24:00 mainland time, not 24:00 local time, so that Easter # Island is always two hours behind the mainland. # From Juan Correa (2016-12-04): # Magallanes region ... will keep DST (UTC -3) all year round.... # http://www.soychile.cl/Santiago/Sociedad/2016/12/04/433428/Bachelet-firmo-el-decreto-para-establecer-un-horario-unico-para-la-Region-de-Magallanes.aspx # From Deborah Goldsmith (2017-01-19): # http://www.diariooficial.interior.gob.cl/publicaciones/2017/01/17/41660/01/1169626.pdf # From Juan Correa (2018-08-13): # As of moments ago, the Ministry of Energy in Chile has announced the new # schema for DST. ... Announcement in video (in Spanish): # https://twitter.com/MinEnergia/status/1029000399129374720 # From Yonathan Dossow (2018-08-13): # The video says "first Saturday of September", we all know it means Sunday at # midnight. # From Tim Parenti (2018-08-13): # Translating the captions on the video at 0:44-0:55, "We want to announce as # Government that from 2019, Winter Time will be increased to 5 months, between # the first Saturday of April and the first Saturday of September." # At 2:08-2:20, "The Magallanes region will maintain its current time, as # decided by the citizens during 2017, but our Government will promote a # regional dialogue table to gather their opinion on this matter." # https://twitter.com/MinEnergia/status/1029009354001973248 # "We will keep the new time policy unchanged for at least the next 4 years." # So we extend the new rules on Saturdays at 24:00 mainland time indefinitely. # From Juan Correa (2019-02-04): # http://www.diariooficial.interior.gob.cl/publicaciones/2018/11/23/42212/01/1498738.pdf # From Paul Eggert (2019-09-01): # The above says the Magallanes exception expires 2022-04-02 at 24:00, # so in theory, they will revert to -04/-03 after that. # For now, assume that they will not revert, # since they have extended the expiration date once already. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Chile 1927 1931 - Sep 1 0:00 1:00 - Rule Chile 1928 1932 - Apr 1 0:00 0 - Rule Chile 1968 only - Nov 3 4:00u 1:00 - Rule Chile 1969 only - Mar 30 3:00u 0 - Rule Chile 1969 only - Nov 23 4:00u 1:00 - Rule Chile 1970 only - Mar 29 3:00u 0 - Rule Chile 1971 only - Mar 14 3:00u 0 - Rule Chile 1970 1972 - Oct Sun>=9 4:00u 1:00 - Rule Chile 1972 1986 - Mar Sun>=9 3:00u 0 - Rule Chile 1973 only - Sep 30 4:00u 1:00 - Rule Chile 1974 1987 - Oct Sun>=9 4:00u 1:00 - Rule Chile 1987 only - Apr 12 3:00u 0 - Rule Chile 1988 1990 - Mar Sun>=9 3:00u 0 - Rule Chile 1988 1989 - Oct Sun>=9 4:00u 1:00 - Rule Chile 1990 only - Sep 16 4:00u 1:00 - Rule Chile 1991 1996 - Mar Sun>=9 3:00u 0 - Rule Chile 1991 1997 - Oct Sun>=9 4:00u 1:00 - Rule Chile 1997 only - Mar 30 3:00u 0 - Rule Chile 1998 only - Mar Sun>=9 3:00u 0 - Rule Chile 1998 only - Sep 27 4:00u 1:00 - Rule Chile 1999 only - Apr 4 3:00u 0 - Rule Chile 1999 2010 - Oct Sun>=9 4:00u 1:00 - Rule Chile 2000 2007 - Mar Sun>=9 3:00u 0 - # N.B.: the end of March 29 in Chile is March 30 in Universal time, # which is used below in specifying the transition. Rule Chile 2008 only - Mar 30 3:00u 0 - Rule Chile 2009 only - Mar Sun>=9 3:00u 0 - Rule Chile 2010 only - Apr Sun>=1 3:00u 0 - Rule Chile 2011 only - May Sun>=2 3:00u 0 - Rule Chile 2011 only - Aug Sun>=16 4:00u 1:00 - Rule Chile 2012 2014 - Apr Sun>=23 3:00u 0 - Rule Chile 2012 2014 - Sep Sun>=2 4:00u 1:00 - Rule Chile 2016 2018 - May Sun>=9 3:00u 0 - Rule Chile 2016 2018 - Aug Sun>=9 4:00u 1:00 - Rule Chile 2019 max - Apr Sun>=2 3:00u 0 - Rule Chile 2019 max - Sep Sun>=2 4:00u 1:00 - # IATA SSIM anomalies: (1992-02) says 1992-03-14; # (1996-09) says 1998-03-08. Ignore these. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Santiago -4:42:46 - LMT 1890 -4:42:46 - SMT 1910 Jan 10 # Santiago Mean Time -5:00 - -05 1916 Jul 1 -4:42:46 - SMT 1918 Sep 10 -4:00 - -04 1919 Jul 1 -4:42:46 - SMT 1927 Sep 1 -5:00 Chile -05/-04 1932 Sep 1 -4:00 - -04 1942 Jun 1 -5:00 - -05 1942 Aug 1 -4:00 - -04 1946 Jul 15 -4:00 1:00 -03 1946 Sep 1 # central Chile -4:00 - -04 1947 Apr 1 -5:00 - -05 1947 May 21 23:00 -4:00 Chile -04/-03 Zone America/Punta_Arenas -4:43:40 - LMT 1890 -4:42:46 - SMT 1910 Jan 10 -5:00 - -05 1916 Jul 1 -4:42:46 - SMT 1918 Sep 10 -4:00 - -04 1919 Jul 1 -4:42:46 - SMT 1927 Sep 1 -5:00 Chile -05/-04 1932 Sep 1 -4:00 - -04 1942 Jun 1 -5:00 - -05 1942 Aug 1 -4:00 - -04 1947 Apr 1 -5:00 - -05 1947 May 21 23:00 -4:00 Chile -04/-03 2016 Dec 4 -3:00 - -03 Zone Pacific/Easter -7:17:28 - LMT 1890 -7:17:28 - EMT 1932 Sep # Easter Mean Time -7:00 Chile -07/-06 1982 Mar 14 3:00u # Easter Time -6:00 Chile -06/-05 # # Salas y Gómez Island is uninhabited. # Other Chilean locations, including Juan Fernández Is, Desventuradas Is, # and Antarctic bases, are like America/Santiago. # Antarctic base using South American rules # (See the file 'antarctica' for more.) # # Palmer, Anvers Island, since 1965 (moved 2 miles in 1968) # # From Ethan Dicks (1996-10-06): # It keeps the same time as Punta Arenas, Chile, because, just like us # and the South Pole, that's the other end of their supply line.... # I verified with someone who was there that since 1980, # Palmer has followed Chile. Prior to that, before the Falklands War, # Palmer used to be supplied from Argentina. # # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone Antarctica/Palmer 0 - -00 1965 -4:00 Arg -04/-03 1969 Oct 5 -3:00 Arg -03/-02 1982 May -4:00 Chile -04/-03 2016 Dec 4 -3:00 - -03 # Colombia # Milne gives 4:56:16.4 for Bogotá time in 1899; round to nearest. He writes, # "A variation of fifteen minutes in the public clocks of Bogota is not rare." # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule CO 1992 only - May 3 0:00 1:00 - Rule CO 1993 only - Apr 4 0:00 0 - # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Bogota -4:56:16 - LMT 1884 Mar 13 -4:56:16 - BMT 1914 Nov 23 # Bogotá Mean Time -5:00 CO -05/-04 # Malpelo, Providencia, San Andres # no information; probably like America/Bogota # Curaçao # See America/Puerto_Rico. # # From Arthur David Olson (2011-06-15): # use links for places with new iso3166 codes. # The name "Lower Prince's Quarter" is both longer than fourteen characters # and contains an apostrophe; use "Lower_Princes".... # From Paul Eggert (2021-05-06): # These backward-compatibility links now are in the 'backward' file. # Ecuador # # Milne says the Central and South American Telegraph Company used -5:24:15. # # From Alois Treindl (2016-12-15): # https://www.elcomercio.com/actualidad/hora-sixto-1993.html # ... Whether the law applied also to Galápagos, I do not know. # From Paul Eggert (2016-12-15): # https://www.elcomercio.com/afull/modificacion-husohorario-ecuador-presidentes-decreto.html # This says President Sixto Durán Ballén signed decree No. 285, which # established DST from 1992-11-28 to 1993-02-05; it does not give transition # times. The people called it "hora de Sixto" ("Sixto hour"). The change did # not go over well; a popular song "Qué hora es" by Jaime Guevara had lyrics # that included "Amanecía en mitad de la noche, los guaguas iban a clase sin # sol" ("It was dawning in the middle of the night, the buses went to class # without sun"). Although Ballén's campaign slogan was "Ni un paso atrás" # (Not one step back), the clocks went back in 1993 and the experiment was not # repeated. For now, assume transitions were at 00:00 local time country-wide. # # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Ecuador 1992 only - Nov 28 0:00 1:00 - Rule Ecuador 1993 only - Feb 5 0:00 0 - # # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Guayaquil -5:19:20 - LMT 1890 -5:14:00 - QMT 1931 # Quito Mean Time -5:00 Ecuador -05/-04 Zone Pacific/Galapagos -5:58:24 - LMT 1931 # Puerto Baquerizo Moreno -5:00 - -05 1986 -6:00 Ecuador -06/-05 # Falklands # From Paul Eggert (2006-03-22): # Between 1990 and 2000 inclusive, Shanks & Pottenger and the IATA agree except # the IATA gives 1996-09-08. Go with Shanks & Pottenger. # From Falkland Islands Government Office, London (2001-01-22) # via Jesper Nørgaard: # ... the clocks revert back to Local Mean Time at 2 am on Sunday 15 # April 2001 and advance one hour to summer time at 2 am on Sunday 2 # September. It is anticipated that the clocks will revert back at 2 # am on Sunday 21 April 2002 and advance to summer time at 2 am on # Sunday 1 September. # From Rives McDow (2001-02-13): # # I have communicated several times with people there, and the last # time I had communications that was helpful was in 1998. Here is # what was said then: # # "The general rule was that Stanley used daylight saving and the Camp # did not. However for various reasons many people in the Camp have # started to use daylight saving (known locally as 'Stanley Time') # There is no rule as to who uses daylight saving - it is a matter of # personal choice and so it is impossible to draw a map showing who # uses it and who does not. Any list would be out of date as soon as # it was produced. This year daylight saving ended on April 18/19th # and started again on September 12/13th. I do not know what the rule # is, but can find out if you like. We do not change at the same time # as UK or Chile." # # I did have in my notes that the rule was "Second Saturday in Sep at # 0:00 until third Saturday in Apr at 0:00". I think that this does # not agree in some cases with Shanks; is this true? # # Also, there is no mention in the list that some areas in the # Falklands do not use DST. I have found in my communications there # that these areas are on the western half of East Falkland and all of # West Falkland. Stanley is the only place that consistently observes # DST. Again, as in other places in the world, the farmers don't like # it. West Falkland is almost entirely sheep farmers. # # I know one lady there that keeps a list of which farm keeps DST and # which doesn't each year. She runs a shop in Stanley, and says that # the list changes each year. She uses it to communicate to her # customers, catching them when they are home for lunch or dinner. # From Paul Eggert (2001-03-05): # For now, we'll just record the time in Stanley, since we have no # better info. # From Steffen Thorsen (2011-04-01): # The Falkland Islands will not turn back clocks this winter, but stay on # daylight saving time. # # One source: # http://www.falklandnews.com/public/story.cfm?get=5914&source=3 # # We have gotten this confirmed by a clerk of the legislative assembly: # Normally the clocks revert to Local Mean Time (UTC/GMT -4 hours) on the # third Sunday of April at 0200hrs and advance to Summer Time (UTC/GMT -3 # hours) on the first Sunday of September at 0200hrs. # # IMPORTANT NOTE: During 2011, on a trial basis, the Falkland Islands # will not revert to local mean time, but clocks will remain on Summer # time (UTC/GMT - 3 hours) throughout the whole of 2011. Any long term # change to local time following the trial period will be notified. # # From Andrew Newman (2012-02-24) # A letter from Justin McPhee, Chief Executive, # Cable & Wireless Falkland Islands (dated 2012-02-22) # states... # The current Atlantic/Stanley entry under South America expects the # clocks to go back to standard Falklands Time (FKT) on the 15th April. # The database entry states that in 2011 Stanley was staying on fixed # summer time on a trial basis only. FIG need to contact IANA and/or # the maintainers of the database to inform them we're adopting # the same policy this year and suggest recommendations for future years. # # For now we will assume permanent -03 for the Falklands # until advised differently (to apply for 2012 and beyond, after the 2011 # experiment was apparently successful.) # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Falk 1937 1938 - Sep lastSun 0:00 1:00 - Rule Falk 1938 1942 - Mar Sun>=19 0:00 0 - Rule Falk 1939 only - Oct 1 0:00 1:00 - Rule Falk 1940 1942 - Sep lastSun 0:00 1:00 - Rule Falk 1943 only - Jan 1 0:00 0 - Rule Falk 1983 only - Sep lastSun 0:00 1:00 - Rule Falk 1984 1985 - Apr lastSun 0:00 0 - Rule Falk 1984 only - Sep 16 0:00 1:00 - Rule Falk 1985 2000 - Sep Sun>=9 0:00 1:00 - Rule Falk 1986 2000 - Apr Sun>=16 0:00 0 - Rule Falk 2001 2010 - Apr Sun>=15 2:00 0 - Rule Falk 2001 2010 - Sep Sun>=1 2:00 1:00 - # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone Atlantic/Stanley -3:51:24 - LMT 1890 -3:51:24 - SMT 1912 Mar 12 # Stanley Mean Time -4:00 Falk -04/-03 1983 May -3:00 Falk -03/-02 1985 Sep 15 -4:00 Falk -04/-03 2010 Sep 5 2:00 -3:00 - -03 # French Guiana # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Cayenne -3:29:20 - LMT 1911 Jul -4:00 - -04 1967 Oct -3:00 - -03 # Guyana # From P Chan (2020-11-27): # https://books.google.com/books?id=5-5CAQAAMAAJ&pg=SA1-PA547 # The Official Gazette of British Guiana. (New Series.) Vol. XL. July to # December, 1915, p 1547, lists as several notes: # "Local Mean Time 3 hours 52 mins. 39 secs. slow of Greenwich Mean Time # (Georgetown.) From 1st August, 1911, British Guiana Standard Mean Time 4 # hours slow of Greenwich Mean Time, by notice in Official Gazette on 1st July, # 1911. From 1st March, 1915, British Guiana Standard Mean Time 3 hours 45 # mins. 0 secs. slow of Greenwich Mean Time, by notice in Official Gazette on # 23rd January, 1915." # # https://parliament.gov.gy/documents/acts/10923-act_no._27_of_1975_-_interpretation_and_general_clauses_(amendment)_act_1975.pdf # Interpretation and general clauses (Amendment) Act 1975 (Act No. 27 of 1975) # [dated 1975-07-31] # "This Act...shall come into operation on 1st August, 1975." # "...where any expression of time occurs...the time referred to shall signify # the standard time of Guyana which shall be three hours behind Greenwich Mean # Time." # # Circular No. 10/1992 dated 1992-03-20 # https://dps.gov.gy/wp-content/uploads/2018/12/1992-03-20-Circular-010.pdf # "...cabinet has decided that with effect from Sunday 29th March, 1992, Guyana # Standard Time would be re-established at 01:00 hours by adjusting the hands # of the clock back to 24:00 hours." # Legislated in the Interpretation and general clauses (Amendment) Act 1992 # (Act No. 6 of 1992) [passed 1992-03-27, published 1992-04-18] # https://parliament.gov.gy/documents/acts/5885-6_of_1992_interpretation_and_general_clauses_(amendment)_act_1992.pdf # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Guyana -3:52:39 - LMT 1911 Aug 1 # Georgetown -4:00 - -04 1915 Mar 1 -3:45 - -0345 1975 Aug 1 -3:00 - -03 1992 Mar 29 1:00 -4:00 - -04 # Paraguay # # From Paul Eggert (2006-03-22): # Shanks & Pottenger say that spring transitions are 01:00 -> 02:00, # and autumn transitions are 00:00 -> 23:00. Go with pre-1999 # editions of Shanks, and with the IATA, who say transitions occur at 00:00. # # From Waldemar Villamayor-Venialbo (2013-09-20): # No time of the day is established for the adjustment, so people normally # adjust their clocks at 0 hour of the given dates. # # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Para 1975 1988 - Oct 1 0:00 1:00 - Rule Para 1975 1978 - Mar 1 0:00 0 - Rule Para 1979 1991 - Apr 1 0:00 0 - Rule Para 1989 only - Oct 22 0:00 1:00 - Rule Para 1990 only - Oct 1 0:00 1:00 - Rule Para 1991 only - Oct 6 0:00 1:00 - Rule Para 1992 only - Mar 1 0:00 0 - Rule Para 1992 only - Oct 5 0:00 1:00 - Rule Para 1993 only - Mar 31 0:00 0 - Rule Para 1993 1995 - Oct 1 0:00 1:00 - Rule Para 1994 1995 - Feb lastSun 0:00 0 - Rule Para 1996 only - Mar 1 0:00 0 - # IATA SSIM (2000-02) says 1999-10-10; ignore this for now. # From Steffen Thorsen (2000-10-02): # I have three independent reports that Paraguay changed to DST this Sunday # (10-01). # # Translated by Gwillim Law (2001-02-27) from # Noticias, a daily paper in Asunción, Paraguay (2000-10-01): # http://www.diarionoticias.com.py/011000/nacional/naciona1.htm # Starting at 0:00 today, the clock will be set forward 60 minutes, in # fulfillment of Decree No. 7,273 of the Executive Power.... The time change # system has been operating for several years. Formerly there was a separate # decree each year; the new law has the same effect, but permanently. Every # year, the time will change on the first Sunday of October; likewise, the # clock will be set back on the first Sunday of March. # Rule Para 1996 2001 - Oct Sun>=1 0:00 1:00 - # IATA SSIM (1997-09) says Mar 1; go with Shanks & Pottenger. Rule Para 1997 only - Feb lastSun 0:00 0 - # Shanks & Pottenger say 1999-02-28; IATA SSIM (1999-02) says 1999-02-27, but # (1999-09) reports no date; go with above sources and Gerd Knops (2001-02-27). Rule Para 1998 2001 - Mar Sun>=1 0:00 0 - # From Rives McDow (2002-02-28): # A decree was issued in Paraguay (No. 16350) on 2002-02-26 that changed the # dst method to be from the first Sunday in September to the first Sunday in # April. Rule Para 2002 2004 - Apr Sun>=1 0:00 0 - Rule Para 2002 2003 - Sep Sun>=1 0:00 1:00 - # # From Jesper Nørgaard Welen (2005-01-02): # There are several sources that claim that Paraguay made # a timezone rule change in autumn 2004. # From Steffen Thorsen (2005-01-05): # Decree 1,867 (2004-03-05) # From Carlos Raúl Perasso via Jesper Nørgaard Welen (2006-10-13) # http://www.presidencia.gov.py/decretos/D1867.pdf Rule Para 2004 2009 - Oct Sun>=15 0:00 1:00 - Rule Para 2005 2009 - Mar Sun>=8 0:00 0 - # From Carlos Raúl Perasso (2010-02-18): # By decree number 3958 issued yesterday # http://www.presidencia.gov.py/v1/wp-content/uploads/2010/02/decreto3958.pdf # Paraguay changes its DST schedule, postponing the March rule to April and # modifying the October date. The decree reads: # ... # Art. 1. It is hereby established that from the second Sunday of the month of # April of this year (2010), the official time is to be set back 60 minutes, # and that on the first Sunday of the month of October, it is to be set # forward 60 minutes, in all the territory of the Paraguayan Republic. # ... Rule Para 2010 max - Oct Sun>=1 0:00 1:00 - Rule Para 2010 2012 - Apr Sun>=8 0:00 0 - # # From Steffen Thorsen (2013-03-07): # Paraguay will end DST on 2013-03-24 00:00.... # http://www.ande.gov.py/interna.php?id=1075 # # From Carlos Raúl Perasso (2013-03-15): # The change in Paraguay is now final. Decree number 10780 # http://www.presidencia.gov.py/uploads/pdf/presidencia-3b86ff4b691c79d4f5927ca964922ec74772ce857c02ca054a52a37b49afc7fb.pdf # From Carlos Raúl Perasso (2014-02-28): # Decree 1264 can be found at: # http://www.presidencia.gov.py/archivos/documentos/DECRETO1264_ey9r8zai.pdf Rule Para 2013 max - Mar Sun>=22 0:00 0 - # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Asuncion -3:50:40 - LMT 1890 -3:50:40 - AMT 1931 Oct 10 # Asunción Mean Time -4:00 - -04 1972 Oct -3:00 - -03 1974 Apr -4:00 Para -04/-03 # Peru # # From Evelyn C. Leeper via Mark Brader (2003-10-26) # : # When we were in Peru in 1985-1986, they apparently switched over # sometime between December 29 and January 3 while we were on the Amazon. # # From Paul Eggert (2006-03-22): # Shanks & Pottenger don't have this transition. Assume 1986 was like 1987. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Peru 1938 only - Jan 1 0:00 1:00 - Rule Peru 1938 only - Apr 1 0:00 0 - Rule Peru 1938 1939 - Sep lastSun 0:00 1:00 - Rule Peru 1939 1940 - Mar Sun>=24 0:00 0 - Rule Peru 1986 1987 - Jan 1 0:00 1:00 - Rule Peru 1986 1987 - Apr 1 0:00 0 - Rule Peru 1990 only - Jan 1 0:00 1:00 - Rule Peru 1990 only - Apr 1 0:00 0 - # IATA is ambiguous for 1993/1995; go with Shanks & Pottenger. Rule Peru 1994 only - Jan 1 0:00 1:00 - Rule Peru 1994 only - Apr 1 0:00 0 - # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Lima -5:08:12 - LMT 1890 -5:08:36 - LMT 1908 Jul 28 # Lima Mean Time? -5:00 Peru -05/-04 # South Georgia # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone Atlantic/South_Georgia -2:26:08 - LMT 1890 # Grytviken -2:00 - -02 # South Sandwich Is # uninhabited; scientific personnel have wintered # Suriname # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Paramaribo -3:40:40 - LMT 1911 -3:40:52 - PMT 1935 # Paramaribo Mean Time -3:40:36 - PMT 1945 Oct # The capital moved? -3:30 - -0330 1984 Oct -3:00 - -03 # Trinidad and Tobago # See America/Puerto_Rico. # Uruguay # From Paul Eggert (1993-11-18): # Uruguay wins the prize for the strangest peacetime manipulation of the rules. # # From Tim Parenti (2018-02-20), per Jeremie Bonjour (2018-01-31) and Michael # Deckers (2018-02-20): # ... At least they kept good records... # # http://www.armada.mil.uy/ContenidosPDFs/sohma/web/almanaque/almanaque_2018.pdf#page=36 # Page 36 of Almanaque 2018, published by the Oceanography, Hydrography, and # Meteorology Service of the Uruguayan Navy, seems to give many transitions # with greater clarity than we've had before. It directly references many laws # and decrees which are, in turn, referenced below. They can be viewed in the # public archives of the Diario Oficial (in Spanish) at # http://www.impo.com.uy/diariooficial/ # # Ley No. 3920 of 1908-06-10 placed the determination of legal time under the # auspices of the National Institute for the Prediction of Time. It is unclear # exactly what offset was used during this period, though Ley No. 7200 of # 1920-04-23 used the Observatory of the National Meteorological Institute in # Montevideo (34° 54' 33" S, 56° 12' 45" W) as its reference meridian, # retarding legal time by 15 minutes 9 seconds from 1920-04-30 24:00, # resulting in UT-04. Assume the corresponding LMT of UT-03:44:51 (given on # page 725 of the Proceedings of the Second Pan-American Scientific Congress, # 1915-1916) was in use, and merely became official from 1908-06-10. # https://www.impo.com.uy/diariooficial/1908/06/18/12 # https://www.impo.com.uy/diariooficial/1920/04/27/9 # # Ley No. 7594 of 1923-06-28 specified legal time as Observatory time advanced # by 44 minutes 51 seconds (UT-03) "from 30 September to 31 March", and by 14 # minutes 51 seconds (UT-03:30) "the rest of the year"; a message from the # National Council of Administration the same day, published directly below the # law in the Diario Oficial, specified the first transition to be 1923-09-30 # 24:00. This effectively established standard time at UT-03:30 with 30 # minutes DST. Assume transitions at 24:00 on the specified days until Ley No. # 7919 of 1926-03-05 ended this arrangement, repealing all "laws and other # provisions which oppose" it, resulting in year-round UT-03:30; a Resolución # of 1926-03-11 puts the final transition at 1926-03-31 24:00, the same as it # would have been under the previous law. # https://www.impo.com.uy/diariooficial/1923/07/02/2 # https://www.impo.com.uy/diariooficial/1926/03/10/2 # https://www.impo.com.uy/diariooficial/1926/03/18/2 # # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Uruguay 1923 1925 - Oct 1 0:00 0:30 - Rule Uruguay 1924 1926 - Apr 1 0:00 0 - # From Tim Parenti (2018-02-15): # http://www.impo.com.uy/diariooficial/1933/10/27/6 # # It appears Ley No. 9122 of 1933 was never published as such in the Diario # Oficial, but instead appeared as Document 26 in the Diario on Friday # 1933-10-27 as a decree made Monday 1933-10-23 and filed under the Ministry of # National Defense. It reinstituted a DST of 30 minutes (to UT-03) "from the # last Sunday of October...until the last Saturday of March." In accordance # with this provision, the first transition was explicitly specified in Article # 2 of the decree as Saturday 1933-10-28 at 24:00; that is, Sunday 1933-10-29 # at 00:00. Assume transitions at 00:00 Sunday throughout. # # Departing from the matter-of-fact nature of previous timekeeping laws, the # 1933 decree "consider[s] the advantages of...the advance of legal time": # # "Whereas: The measure adopted by almost all nations at the time of the last # World War still persists in North America and Europe, precisely because of # the economic, hygienic, and social advantages derived from such an # emergency measure... # # Whereas: The advance of the legal time during the summer seasons, by # displacing social activity near sunrise, favors the citizen populations # and especially the society that creates and works..." # # It further specified that "necessary measures" be taken to ensure that # "public spectacles finish, in general, before [01:00]." Rule Uruguay 1933 1938 - Oct lastSun 0:00 0:30 - Rule Uruguay 1934 1941 - Mar lastSat 24:00 0 - # From Tim Parenti (2018-02-15): # Most of the Rules below, and their contemporaneous Zone lines, have been # updated simply to match the Almanaque 2018. Although the document does not # list exact transition times, midnight transitions were already present in our # data here for all transitions through 2004-09, and this is both consistent # with prior transitions and verified in several decrees marked below between # 1939-09 and 2004-09, wherein the relevant text was typically of the form: # # "From 0 hours on [date], the legal time of the entire Republic will be... # # In accordance with [the preceding], on [previous date] at 24 hours, all # clocks throughout the Republic will be [advanced/retarded] by..." # # It is possible that there is greater specificity to be found for the Rules # below, but it is buried in no fewer than 40 different decrees individually # referenced by the Almanaque for the period from 1939-09 to 2014-09. # Four-fifths of these were promulgated less than two weeks before taking # effect; more than half within a week and none more than 5 weeks. Only the # handful with comments below have been checked with any thoroughness. Rule Uruguay 1939 only - Oct 1 0:00 0:30 - Rule Uruguay 1940 only - Oct 27 0:00 0:30 - # From Tim Parenti (2018-02-15): # Decreto 1145 of the Ministry of National Defense, dated 1941-07-26, specified # UT-03 from Friday 1941-08-01 00:00, citing an "urgent...need to save fuel". # http://www.impo.com.uy/diariooficial/1941/08/04/1 Rule Uruguay 1941 only - Aug 1 0:00 0:30 - # From Tim Parenti (2018-02-15): # Decreto 1866 of the Ministry of National Defense, dated 1942-12-09, specified # further advancement (to UT-02:30) from Sunday 1942-12-13 24:00. Since clocks # never went back to UT-03:30 thereafter, this is modeled as advancing standard # time by 30 minutes to UT-03, while retaining 30 minutes of DST. # http://www.impo.com.uy/diariooficial/1942/12/16/3 Rule Uruguay 1942 only - Dec 14 0:00 0:30 - Rule Uruguay 1943 only - Mar 14 0:00 0 - Rule Uruguay 1959 only - May 24 0:00 0:30 - Rule Uruguay 1959 only - Nov 15 0:00 0 - Rule Uruguay 1960 only - Jan 17 0:00 1:00 - Rule Uruguay 1960 only - Mar 6 0:00 0 - Rule Uruguay 1965 only - Apr 4 0:00 1:00 - Rule Uruguay 1965 only - Sep 26 0:00 0 - # From Tim Parenti (2018-02-15): # Decreto 321/968 of 1968-05-25, citing emergency drought measures decreed the # day before, brought clocks forward 30 minutes from Monday 1968-05-27 00:00. # http://www.impo.com.uy/diariooficial/1968/05/30/5 Rule Uruguay 1968 only - May 27 0:00 0:30 - Rule Uruguay 1968 only - Dec 1 0:00 0 - # From Tim Parenti (2018-02-15): # Decreto 188/970 of 1970-04-23 instituted restrictions on electricity # consumption "as a consequence of the current rainfall regime in the country". # Articles 13 and 14 advanced clocks by an hour from Saturday 1970-04-25 00:00. # http://www.impo.com.uy/diariooficial/1970/04/29/4 Rule Uruguay 1970 only - Apr 25 0:00 1:00 - Rule Uruguay 1970 only - Jun 14 0:00 0 - Rule Uruguay 1972 only - Apr 23 0:00 1:00 - Rule Uruguay 1972 only - Jul 16 0:00 0 - # From Tim Parenti (2018-02-15): # Decreto 29/974 of 1974-01-11, citing "the international rise in the price of # oil", advanced clocks by 90 minutes (to UT-01:30). Decreto 163/974 of # 1974-03-04 returned 60 of those minutes (to UT-02:30), and the remaining 30 # minutes followed in Decreto 679/974 of 1974-08-29. # http://www.impo.com.uy/diariooficial/1974/01/22/11 # http://www.impo.com.uy/diariooficial/1974/03/14/3 # http://www.impo.com.uy/diariooficial/1974/09/04/6 Rule Uruguay 1974 only - Jan 13 0:00 1:30 - Rule Uruguay 1974 only - Mar 10 0:00 0:30 - Rule Uruguay 1974 only - Sep 1 0:00 0 - Rule Uruguay 1974 only - Dec 22 0:00 1:00 - Rule Uruguay 1975 only - Mar 30 0:00 0 - Rule Uruguay 1976 only - Dec 19 0:00 1:00 - Rule Uruguay 1977 only - Mar 6 0:00 0 - Rule Uruguay 1977 only - Dec 4 0:00 1:00 - Rule Uruguay 1978 1979 - Mar Sun>=1 0:00 0 - Rule Uruguay 1978 only - Dec 17 0:00 1:00 - Rule Uruguay 1979 only - Apr 29 0:00 1:00 - Rule Uruguay 1980 only - Mar 16 0:00 0 - # From Tim Parenti (2018-02-15): # Decreto 725/987 of 1987-12-04 cited "better use of national tourist # attractions" to advance clocks one hour from Monday 1987-12-14 00:00. # http://www.impo.com.uy/diariooficial/1988/01/25/1 Rule Uruguay 1987 only - Dec 14 0:00 1:00 - Rule Uruguay 1988 only - Feb 28 0:00 0 - Rule Uruguay 1988 only - Dec 11 0:00 1:00 - Rule Uruguay 1989 only - Mar 5 0:00 0 - Rule Uruguay 1989 only - Oct 29 0:00 1:00 - Rule Uruguay 1990 only - Feb 25 0:00 0 - # From Tim Parenti (2018-02-15), per Paul Eggert (1999-11-04): # IATA agrees as below for 1990-10 through 1993-02. Per Almanaque 2018, the # 1992/1993 season appears to be the first in over half a century where DST # both began and ended pursuant to the same decree. Rule Uruguay 1990 1991 - Oct Sun>=21 0:00 1:00 - Rule Uruguay 1991 1992 - Mar Sun>=1 0:00 0 - Rule Uruguay 1992 only - Oct 18 0:00 1:00 - Rule Uruguay 1993 only - Feb 28 0:00 0 - # From Eduardo Cota (2004-09-20): # The Uruguayan government has decreed a change in the local time.... # From Tim Parenti (2018-02-15): # Decreto 328/004 of 2004-09-15. # http://www.impo.com.uy/diariooficial/2004/09/23/documentos.pdf#page=1 Rule Uruguay 2004 only - Sep 19 0:00 1:00 - # From Steffen Thorsen (2005-03-11): # Uruguay's DST was scheduled to end on Sunday, 2005-03-13, but in order to # save energy ... it was postponed two weeks.... # From Tim Parenti (2018-02-15): # This 2005 postponement is not in Almanaque 2018. Go with the contemporaneous # reporting, which is confirmed by Decreto 107/005 of 2005-03-10 amending # Decreto 328/004: # http://www.impo.com.uy/diariooficial/2005/03/15/documentos.pdf#page=1 # The original decree specified a transition of 2005-03-12 24:00, but the new # one specified 2005-03-27 02:00. Rule Uruguay 2005 only - Mar 27 2:00 0 - # From Eduardo Cota (2005-09-27): # ...from 2005-10-09 at 02:00 local time, until 2006-03-12 at 02:00 local time, # official time in Uruguay will be at GMT -2. # From Tim Parenti (2018-02-15): # Decreto 318/005 of 2005-09-19. # http://www.impo.com.uy/diariooficial/2005/09/23/documentos.pdf#page=1 Rule Uruguay 2005 only - Oct 9 2:00 1:00 - Rule Uruguay 2006 2015 - Mar Sun>=8 2:00 0 - # From Tim Parenti (2018-02-15), per Jesper Nørgaard Welen (2006-09-06): # Decreto 311/006 of 2006-09-04 established regular DST from the first Sunday # of October at 02:00 through the second Sunday of March at 02:00. Almanaque # 2018 appears to have a few typoed dates through this period; ignore them. # http://www.impo.com.uy/diariooficial/2006/09/08/documentos.pdf#page=1 Rule Uruguay 2006 2014 - Oct Sun>=1 2:00 1:00 - # From Steffen Thorsen (2015-06-30): # ... it looks like they will not be using DST the coming summer: # http://www.elobservador.com.uy/gobierno-resolvio-que-no-habra-cambio-horario-verano-n656787 # http://www.republica.com.uy/este-ano-no-se-modificara-el-huso-horario-en-uruguay/523760/ # From Paul Eggert (2015-06-30): # Apparently restaurateurs complained that DST caused people to go to the beach # instead of out to dinner. # From Pablo Camargo (2015-07-13): # http://archivo.presidencia.gub.uy/sci/decretos/2015/06/cons_min_201.pdf # From Tim Parenti (2018-02-15): # Decreto 178/015 of 2015-06-29; repeals Decreto 311/006. # This Zone can be simplified once we assume zic %z. Zone America/Montevideo -3:44:51 - LMT 1908 Jun 10 -3:44:51 - MMT 1920 May 1 # Montevideo MT -4:00 - -04 1923 Oct 1 -3:30 Uruguay -0330/-03 1942 Dec 14 -3:00 Uruguay -03/-0230 1960 -3:00 Uruguay -03/-02 1968 -3:00 Uruguay -03/-0230 1970 -3:00 Uruguay -03/-02 1974 -3:00 Uruguay -03/-0130 1974 Mar 10 -3:00 Uruguay -03/-0230 1974 Dec 22 -3:00 Uruguay -03/-02 # Venezuela # # From Paul Eggert (2015-07-28): # For the 1965 transition see Gaceta Oficial No. 27.619 (1964-12-15), p 205.533 # http://www.pgr.gob.ve/dmdocuments/1964/27619.pdf # # From John Stainforth (2007-11-28): # ... the change for Venezuela originally expected for 2007-12-31 has # been brought forward to 2007-12-09. The official announcement was # published today in the "Gaceta Oficial de la República Bolivariana # de Venezuela, número 38.819" (official document for all laws or # resolution publication) # http://www.globovision.com/news.php?nid=72208 # From Alexander Krivenyshev (2016-04-15): # https://actualidad.rt.com/actualidad/204758-venezuela-modificar-huso-horario-sequia-elnino # # From Paul Eggert (2016-04-15): # Clocks advance 30 minutes on 2016-05-01 at 02:30.... # "'Venezuela's new time-zone: hours without light, hours without water, # hours of presidential broadcasts, hours of lines,' quipped comedian # Jean Mary Curró ...". See: Cawthorne A, Kai D. Venezuela scraps # half-hour time difference set by Chavez. Reuters 2016-04-15 14:50 -0400 # https://www.reuters.com/article/us-venezuela-timezone-idUSKCN0XC2BE # # From Matt Johnson (2016-04-20): # ... published in the official Gazette [2016-04-18], here: # http://historico.tsj.gob.ve/gaceta_ext/abril/1842016/E-1842016-4551.pdf # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Caracas -4:27:44 - LMT 1890 -4:27:40 - CMT 1912 Feb 12 # Caracas Mean Time? -4:30 - -0430 1965 Jan 1 0:00 -4:00 - -04 2007 Dec 9 3:00 -4:30 - -0430 2016 May 1 2:30 -4:00 - -04