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5722 Update timezone info db to 2015a
@@ -122,11 +122,11 @@
# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
Rule US 1918 1919 - Mar lastSun 2:00 1:00 D
Rule US 1918 1919 - Oct lastSun 2:00 0 S
Rule US 1942 only - Feb 9 2:00 1:00 W # War
Rule US 1945 only - Aug 14 23:00u 1:00 P # Peace
-Rule US 1945 only - Sep 30 2:00 0 S
+Rule US 1945 only - Sep lastSun 2:00 0 S
Rule US 1967 2006 - Oct lastSun 2:00 0 S
Rule US 1967 1973 - Apr lastSun 2:00 1:00 D
Rule US 1974 only - Jan 6 2:00 1:00 D
Rule US 1975 only - Feb 23 2:00 1:00 D
Rule US 1976 1986 - Apr lastSun 2:00 1:00 D
@@ -275,10 +275,16 @@
# set their watches and clocks on Eastern time." It quotes H.H. "Bubba"
# Roberts, city administrator in Phenix City. as saying "We are in the Central
# time zone, but we do go by the Eastern time zone because so many people work
# in Columbus."
+# From Paul Eggert (2014-09-06):
+# Monthly Notices of the Royal Astronomical Society 44, 4 (1884-02-08), 208
+# says that New York City Hall time was 3 minutes 58.4 seconds fast of
+# Eastern time (i.e., -4:56:01.6) just before the 1883 switch. Round to the
+# nearest second.
+
# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
Rule NYC 1920 only - Mar lastSun 2:00 1:00 D
Rule NYC 1920 only - Oct lastSun 2:00 0 S
Rule NYC 1921 1966 - Apr lastSun 2:00 1:00 D
Rule NYC 1921 1954 - Sep lastSun 2:00 0 S
@@ -983,24 +989,24 @@
# Jimmy Skaggs, _The Great Guano Rush_ (1994).
################################################################################
-# From Paul Eggert (2006-03-22):
-# A good source for time zone historical data outside the U.S. is
+# From Paul Eggert (2014-10-31):
+#
+# 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.
#
# Gwillim Law writes that a good source
# for recent time zone data is 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.
+# of the IATA's data after 1990. Except where otherwise noted,
+# IATA SSIM is the source for entries after 1990.
#
-# Except where otherwise noted, Shanks & Pottenger is the source for
-# entries through 1990, and IATA SSIM is the source for entries afterwards.
-#
# Other sources occasionally used include:
#
# Edward W. Whitman, World Time Differences,
# Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated),
# which I found in the UCLA library.
@@ -1093,21 +1099,20 @@
# ...
# Nunavut
# An amendment to the Interpretation Act was registered on February 19/2007....
# http://action.attavik.ca/home/justice-gn/attach/2007/gaz02part2.pdf
-# From Paul Eggert (2006-04-25):
+# From Paul Eggert (2014-10-18):
# H. David Matthews and Mary Vincent's map
# "It's about TIME", _Canadian Geographic_ (September-October 1998)
-# http://www.canadiangeographic.ca/Magazine/SO98/geomap.asp
+# http://www.canadiangeographic.ca/Magazine/SO98/alacarte.asp
# contains detailed boundaries for regions observing nonstandard
# time and daylight saving time arrangements in Canada circa 1998.
#
-# INMS, the Institute for National Measurement Standards in Ottawa, has
-# information about standard and daylight saving time zones in Canada.
-# http://inms-ienm.nrc-cnrc.gc.ca/en/time_services/daylight_saving_e.php
-# (updated periodically).
+# National Research Council Canada maintains info about time zones and DST.
+# http://www.nrc-cnrc.gc.ca/eng/services/time/time_zones.html
+# http://www.nrc-cnrc.gc.ca/eng/services/time/faq/index.html#Q5
# Its unofficial information is often taken from Matthews and Vincent.
# From Paul Eggert (2006-06-27):
# For now, assume all of DST-observing Canada will fall into line with the
# new US DST rules,
@@ -1968,25 +1973,24 @@
# checking for more info, and will get back to you if I come up with
# more.
# [Also see <http://www.nunatsiaq.com/nunavut/nvt10309_06.html> (2001-03-09).]
# From Gwillim Law (2005-05-21):
-# According to maps at
-# http://inms-ienm.nrc-cnrc.gc.ca/images/time_services/TZ01SWE.jpg
-# http://inms-ienm.nrc-cnrc.gc.ca/images/time_services/TZ01SSE.jpg
-# (both dated 2003), and
+# According to ...
# http://www.canadiangeographic.ca/Magazine/SO98/geomap.asp
# (from a 1998 Canadian Geographic article), the de facto and de jure time
# for Southampton Island (at the north end of Hudson Bay) is UTC-5 all year
# round. Using Google, it's easy to find other websites that confirm this.
# I wasn't able to find how far back this time regimen goes, but since it
# predates the creation of Nunavut, it probably goes back many years....
# The Inuktitut name of Coral Harbour is Sallit, but it's rarely used.
#
-# From Paul Eggert (2005-07-26):
+# From Paul Eggert (2014-10-17):
# For lack of better information, assume that Southampton Island observed
-# daylight saving only during wartime.
+# daylight saving only during wartime. Gwillim Law's email also
+# mentioned maps now maintained by National Research Council Canada;
+# see above for an up-to-date link.
# From Chris Walton (2007-03-01):
# ... the community of Resolute (located on Cornwallis Island in
# Nunavut) moved from Central Time to Eastern Time last November.
# Basically the community did not change its clocks at the end of
@@ -2118,15 +2122,15 @@
###############################################################################
# Mexico
-# From Paul Eggert (2001-03-05):
+# From Paul Eggert (2014-12-07):
# The Investigation and Analysis Service of the
# Mexican Library of Congress (MLoC) has published a
# history of Mexican local time (in Spanish)
-# http://www.cddhcu.gob.mx/bibliot/publica/inveyana/polisoc/horver/
+# http://www.diputados.gob.mx/bibliot/publica/inveyana/polisoc/horver/index.htm
#
# Here are the discrepancies between Shanks & Pottenger (S&P) and the MLoC.
# (In all cases we go with the MLoC.)
# S&P report that Baja was at -8:00 in 1922/1923.
# S&P say the 1930 transition in Baja was 1930-11-16.
@@ -2291,10 +2295,28 @@
# kilómetros, así como la Ciudad de Ensenada, Baja California, hacia el
# interior del país, la aplicación de este horario estacional surtirá
# efecto desde las dos horas del segundo domingo de marzo y concluirá a
# las dos horas del primer domingo de noviembre.
+# From Steffen Thorsen (2014-12-08), translated by Gwillim Law:
+# The Mexican state of Quintana Roo will likely change to EST in 2015.
+#
+# http://www.unioncancun.mx/articulo/2014/12/04/medio-ambiente/congreso-aprueba-una-hora-mas-de-sol-en-qroo
+# "With this change, the time conflict that has existed between the municipios
+# of Quintana Roo and the municipio of Felipe Carrillo Puerto may come to an
+# end. The latter declared itself in rebellion 15 years ago when a time change
+# was initiated in Mexico, and since then it has refused to change its time
+# zone along with the rest of the country."
+#
+# From Steffen Thorsen (2015-01-14), translated by Gwillim Law:
+# http://sipse.com/novedades/confirman-aplicacion-de-nueva-zona-horaria-para-quintana-roo-132331.html
+# "...the new time zone will come into effect at two o'clock on the first Sunday
+# of February, when we will have to advance the clock one hour from its current
+# time..."
+#
+# Also, the new zone will not use DST.
+
# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
Rule Mexico 1939 only - Feb 5 0:00 1:00 D
Rule Mexico 1939 only - Jun 25 0:00 0 S
Rule Mexico 1940 only - Dec 9 0:00 1:00 D
Rule Mexico 1941 only - Apr 1 0:00 0 S
@@ -2311,11 +2333,12 @@
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
# Quintana Roo; represented by Cancún
Zone America/Cancun -5:47:04 - LMT 1922 Jan 1 0:12:56
-6:00 - CST 1981 Dec 23
-5:00 Mexico E%sT 1998 Aug 2 2:00
- -6:00 Mexico C%sT
+ -6:00 Mexico C%sT 2015 Feb 1 2:00
+ -5:00 - EST
# Campeche, Yucatán; represented by Mérida
Zone America/Merida -5:58:28 - LMT 1922 Jan 1 0:01:32
-6:00 - CST 1981 Dec 23
-5:00 - EST 1982 Dec 2
-6:00 Mexico C%sT
@@ -2983,14 +3006,25 @@
# Jamaica
# Shanks & Pottenger give -5:07:12, but Milne records -5:07:10.41 from an
# unspecified official document, and says "This time is used throughout the
# island". Go with Milne. Round to the nearest second as required by zic.
+#
+# Shanks & Pottenger give April 28 for the 1974 spring-forward transition, but
+# Lance Neita writes that Prime Minister Michael Manley decreed it January 5.
+# Assume Neita meant Jan 6 02:00, the same as the US. Neita also writes that
+# Manley's supporters associated this act with Manley's nickname "Joshua"
+# (recall that in the Bible the sun stood still at Joshua's request),
+# and with the Rod of Correction which Manley said he had received from
+# Haile Selassie, Emperor of Ethiopia. See:
+# Neita L. The politician in all of us. Jamaica Observer 2014-09-20
+# http://www.jamaicaobserver.com/columns/The-politician-in-all-of-us_17573647
+#
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
Zone America/Jamaica -5:07:11 - LMT 1890 # Kingston
-5:07:11 - KMT 1912 Feb # Kingston Mean Time
- -5:00 - EST 1974 Apr 28 2:00
+ -5:00 - EST 1974
-5:00 US E%sT 1984
-5:00 - EST
# Martinique
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
@@ -3114,17 +3148,21 @@
# indicating that the normal ET rules are followed.
#
# From Paul Eggert (2014-08-19):
# The 2014-08-13 Cabinet meeting decided to stay on UTC-4 year-round. See:
# http://tcweeklynews.com/daylight-savings-time-to-be-maintained-p5353-127.htm
-# Model this as a switch from EST/EDT to AST on 2014-11-02 at 02:00.
+# Model this as a switch from EST/EDT to AST ...
+# From Chris Walton (2014-11-04):
+# ... the TCI government appears to have delayed the switch to
+# "permanent daylight saving time" by one year....
+# http://tcweeklynews.com/time-change-to-go-ahead-this-november-p5437-127.htm
#
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
Zone America/Grand_Turk -4:44:32 - LMT 1890
-5:07:11 - KMT 1912 Feb # Kingston Mean Time
-5:00 - EST 1979
- -5:00 US E%sT 2014 Nov 2 2:00
+ -5:00 US E%sT 2015 Nov Sun>=1 2:00
-4:00 - AST
# British Virgin Is
# Virgin Is
# See America/Port_of_Spain.