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7481 Update zoneinfo to 2016h
@@ -22,13 +22,37 @@
# Principal of Temple Grove Ladies' Seminary (Saratoga Springs, NY).
# His pamphlet "A System of National Time for Railroads" (1870)
# was the result of his proposals at the Convention of Railroad Trunk Lines
# in New York City (1869-10). His 1870 proposal was based on Washington, DC,
# but in 1872-05 he moved the proposed origin to Greenwich.
-# His proposal was adopted by the railroads on 1883-11-18 at 12:00,
-# and the most of the country soon followed suit.
+# From Paul Eggert (2016-09-21):
+# Dowd's proposal left many details unresolved, such as where to draw
+# lines between time zones. The key individual who made time zones
+# work in the US was William Frederick Allen - railway engineer,
+# managing editor of the Travelers' Guide, and secretary of the
+# General Time Convention, a railway standardization group. Allen
+# spent months in dialogs with scientific and railway leaders,
+# developed a workable plan to institute time zones, and presented it
+# to the General Time Convention on 1883-04-11, saying that his plan
+# meant "local time would be practically abolished" - a plus for
+# railway scheduling. By the next convention on 1883-10-11 nearly all
+# railroads had agreed and it took effect on 1883-11-18 at 12:00.
+# That Sunday was called the "day of two noons", as the eastern parts
+# of the new zones observed noon twice. Allen witnessed the
+# transition in New York City, writing:
+#
+# I heard the bells of St. Paul's strike on the old time. Four
+# minutes later, obedient to the electrical signal from the Naval
+# Observatory ... the time-ball made its rapid descent, the chimes
+# of old Trinity rang twelve measured strokes, and local time was
+# abandoned, probably forever.
+#
+# Most of the US soon followed suit. See:
+# Bartky IR. The adoption of standard time. Technol Cult 1989 Jan;30(1):25-56.
+# http://dx.doi.org/10.2307/3105430
+
# From Paul Eggert (2005-04-16):
# That 1883 transition occurred at 12:00 new time, not at 12:00 old time.
# See p 46 of David Prerau, Seize the daylight, Thunder's Mouth Press (2005).
# From Paul Eggert (2006-03-22):
@@ -411,15 +435,46 @@
# California, northern Idaho (Benewah, Bonner, Boundary, Clearwater,
# Kootenai, Latah, Lewis, Nez Perce, and Shoshone counties, Idaho county
# north of the Salmon River, and the towns of Burgdorf and Warren),
# Nevada (except West Wendover), Oregon (except the northern 3/4 of
# Malheur county), and Washington
+
+# From Paul Eggert (2016-08-20):
+# In early February 1948, in response to California's electricity shortage,
+# PG&E changed power frequency from 60 to 59.5 Hz during daylight hours,
+# causing electric clocks to lose six minutes per day. (This did not change
+# legal time, and is not part of the data here.) See:
+# Ross SA. An energy crisis from the past: Northern California in 1948.
+# Working Paper No. 8, Institute of Governmental Studies, UC Berkeley,
+# 1973-11. http://escholarship.org/uc/item/8x22k30c
#
+# In another measure to save electricity, DST was instituted from 1948-03-14
+# at 02:01 to 1949-01-16 at 02:00, with the governor having the option to move
+# the fallback transition earlier. See pages 3-4 of:
+# http://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1948/48Vol1_Chapters.pdf
+#
+# In response:
+#
+# Governor Warren received a torrent of objecting mail, and it is not too much
+# to speculate that the objections to Daylight Saving Time were one important
+# factor in the defeat of the Dewey-Warren Presidential ticket in California.
+# -- Ross, p 25
+#
+# On December 8 the governor exercised the option, setting the date to January 1
+# (LA Times 1948-12-09). The transition time was 02:00 (LA Times 1949-01-01).
+#
+# Despite the controversy, in 1949 California voters approved Proposition 12,
+# which established DST from April's last Sunday at 01:00 until September's
+# last Sunday at 02:00. This was amended by 1962's Proposition 6, which changed
+# the fall-back date to October's last Sunday. See:
+# http://repository.uchastings.edu/cgi/viewcontent.cgi?article=1501&context=ca_ballot_props
+# http://repository.uchastings.edu/cgi/viewcontent.cgi?article=1636&context=ca_ballot_props
+#
# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
-Rule CA 1948 only - Mar 14 2:00 1:00 D
+Rule CA 1948 only - Mar 14 2:01 1:00 D
Rule CA 1949 only - Jan 1 2:00 0 S
-Rule CA 1950 1966 - Apr lastSun 2:00 1:00 D
+Rule CA 1950 1966 - Apr lastSun 1:00 1:00 D
Rule CA 1950 1961 - Sep lastSun 2:00 0 S
Rule CA 1962 1966 - Oct lastSun 2:00 0 S
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 12:07:02
-8:00 US P%sT 1946
@@ -2189,43 +2244,43 @@
Rule NT_YK 1980 1986 - Apr lastSun 2:00 1:00 D
Rule NT_YK 1980 2006 - Oct lastSun 2:00 0 S
Rule NT_YK 1987 2006 - Apr Sun>=1 2:00 1:00 D
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
# aka Panniqtuuq
-Zone America/Pangnirtung 0 - zzz 1921 # trading post est.
+Zone America/Pangnirtung 0 - -00 1921 # trading post est.
-4:00 NT_YK A%sT 1995 Apr Sun>=1 2:00
-5:00 Canada E%sT 1999 Oct 31 2:00
-6:00 Canada C%sT 2000 Oct 29 2:00
-5:00 Canada E%sT
# formerly Frobisher Bay
-Zone America/Iqaluit 0 - zzz 1942 Aug # Frobisher Bay est.
+Zone America/Iqaluit 0 - -00 1942 Aug # Frobisher Bay est.
-5:00 NT_YK E%sT 1999 Oct 31 2:00
-6:00 Canada C%sT 2000 Oct 29 2:00
-5:00 Canada E%sT
# aka Qausuittuq
-Zone America/Resolute 0 - zzz 1947 Aug 31 # Resolute founded
+Zone America/Resolute 0 - -00 1947 Aug 31 # Resolute founded
-6:00 NT_YK C%sT 2000 Oct 29 2:00
-5:00 - EST 2001 Apr 1 3:00
-6:00 Canada C%sT 2006 Oct 29 2:00
-5:00 - EST 2007 Mar 11 3:00
-6:00 Canada C%sT
# aka Kangiqiniq
-Zone America/Rankin_Inlet 0 - zzz 1957 # Rankin Inlet founded
+Zone America/Rankin_Inlet 0 - -00 1957 # Rankin Inlet founded
-6:00 NT_YK C%sT 2000 Oct 29 2:00
-5:00 - EST 2001 Apr 1 3:00
-6:00 Canada C%sT
# aka Iqaluktuuttiaq
-Zone America/Cambridge_Bay 0 - zzz 1920 # trading post est.?
+Zone America/Cambridge_Bay 0 - -00 1920 # trading post est.?
-7:00 NT_YK M%sT 1999 Oct 31 2:00
-6:00 Canada C%sT 2000 Oct 29 2:00
-5:00 - EST 2000 Nov 5 0:00
-6:00 - CST 2001 Apr 1 3:00
-7:00 Canada M%sT
-Zone America/Yellowknife 0 - zzz 1935 # Yellowknife founded?
+Zone America/Yellowknife 0 - -00 1935 # Yellowknife founded?
-7:00 NT_YK M%sT 1980
-7:00 Canada M%sT
-Zone America/Inuvik 0 - zzz 1953 # Inuvik founded
+Zone America/Inuvik 0 - -00 1953 # Inuvik founded
-8:00 NT_YK P%sT 1979 Apr lastSun 2:00
-7:00 NT_YK M%sT 1980
-7:00 Canada M%sT
Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20
-9:00 NT_YK Y%sT 1967 May 28 0:00
@@ -2474,10 +2529,19 @@
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
# Coahuila, Nuevo León, Tamaulipas (near US border)
+# This includes the following municipalities:
+# in Coahuila: Ocampo, Acuña, Zaragoza, Jiménez, Piedras Negras, Nava,
+# Guerrero, Hidalgo.
+# in Nuevo León: Anáhuac, Los Aldama.
+# in Tamaulipas: Nuevo Laredo, Guerrero, Mier, Miguel Alemán, Camargo,
+# Gustavo Díaz Ordaz, Reynosa, Río Bravo, Valle Hermoso, Matamoros.
+# See: Inicia mañana Horario de Verano en zona fronteriza, El Universal,
+# 2016-03-12
+# http://www.eluniversal.com.mx/articulo/estados/2016/03/12/inicia-manana-horario-de-verano-en-zona-fronteriza
Zone America/Matamoros -6:40:00 - LMT 1921 Dec 31 23:20:00
-6:00 - CST 1988
-6:00 US C%sT 1989
-6:00 Mexico C%sT 2010
-6:00 US C%sT
@@ -2495,10 +2559,13 @@
-7:00 - MST 1932 Apr 1
-6:00 Mexico C%sT 2001 Sep 30 2:00
-6:00 - CST 2002 Feb 20
-6:00 Mexico C%sT
# Chihuahua (near US border)
+# This includes the municipalities of Janos, Ascensión, Juárez, Guadalupe,
+# Práxedis G Guerrero, Coyame del Sotol, Ojinaga, and Manuel Benavides.
+# (See the 2016-03-12 El Universal source mentioned above.)
Zone America/Ojinaga -6:57:40 - LMT 1922 Jan 1 0:02:20
-7:00 - MST 1927 Jun 10 23:00
-6:00 - CST 1930 Nov 15
-7:00 - MST 1931 May 1 23:00
-6:00 - CST 1931 Oct
@@ -3267,11 +3334,11 @@
# "Eastern Standard Times Begins 2007
# Clocks are set back one hour at 2:00 a.m. local Daylight Saving Time"
# 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:
+# The 2014-08-13 Cabinet meeting decided to stay on UT -04 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 ...
# From Chris Walton (2014-11-04):
# ... the TCI government appears to have delayed the switch to
# "permanent daylight saving time" by one year....