[tz] [PROPOSED PATCH 1/4] Prefer +-NN notation for UT-offset time zones in comments.
eggert at cs.ucla.edu
Thu Aug 25 04:42:19 UTC 2016
Robert Elz wrote:
> I think UTC-1 is both more common, and less ambiguous than -01
You make a good point that "UTC-1" is less ambiguous in general English text.
Unfortunately in tzdata commentary "UTC-1" is often not technically correct, as
UTC is not defined for older time stamps.
With this in mind, how about if we change that commentary to use "UT -01"
instead, as in the attached proposed patch. This should be clear enough within
the tzdata context. The space after the "UT" encourages shorthands like "switch
from UT -09 to -08" without having to repeat the "UT" all the time.
> | -# Zhongyuan Time ("Central plain Time") UT+8
> | +# Zhongyuan Time ("Central plain Time") -08
> cannot be right.
Thanks, good catch. Also fixed in the attached.
-------------- next part --------------
From 78ca3a3151a322df89e852fa04cfafaf8fd9d93e Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert at cs.ucla.edu>
Date: Wed, 24 Aug 2016 21:38:33 -0700
Subject: [PROPOSED PATCH] Prefer UT +-NN notation for UT-offset time zones in
This does not change any code or data; just comments.
NEWS | 42 +++++++++++++++++++++---------------------
Theory | 2 +-
africa | 2 +-
antarctica | 2 +-
asia | 32 ++++++++++++++++----------------
australasia | 18 +++++++++---------
backzone | 8 ++++----
europe | 2 +-
northamerica | 2 +-
9 files changed, 55 insertions(+), 55 deletions(-)
diff --git a/NEWS b/NEWS
index 7b105da..7882484 100644
@@ -487,7 +487,7 @@ Release 2015d - 2015-04-24 08:09:46 -0700
Changes affecting past time stamps
- America/Whitehorse switched from -09 to -08 on 1967-05-28, not
+ America/Whitehorse switched from UT -09 to -08 on 1967-05-28, not
1966-07-01. Also, Yukon's time zone history is documented better.
(Thanks to Brian Inglis and Dennis Ferguson.)
@@ -521,12 +521,12 @@ Release 2015c - 2015-04-11 08:55:55 -0700
The 1918 transition was September 10, not September 1.
- The -04 time observed from 1932 to 1942 is now considered to be
- standard time, not year-round DST.
+ The UT -04 time observed from 1932 to 1942 is now considered to
+ be standard time, not year-round DST.
- Santiago observed DST (-03) from 1946-07-15 through 1946-08-31,
- then reverted to standard time, then switched its time zone to
- -05 on 1947-04-01.
+ Santiago observed DST (UT -03) from 1946-07-15 through
+ 1946-08-31, then reverted to standard time, then switched to -05
+ on 1947-04-01.
Assume transitions before 1968 were at 00:00, since we have no data
@@ -655,7 +655,7 @@ Release 2014j - 2014-11-10 17:37:11 -0800
Changes affecting current and future time stamps
- Turks & Caicos' switch from US eastern time to -04 year-round
+ Turks & Caicos' switch from US eastern time to UT -04 year-round
did not occur on 2014-11-02 at 02:00. It's currently scheduled
for 2015-11-01 at 02:00. (Thanks to Chris Walton.)
@@ -691,7 +691,7 @@ Release 2014i - 2014-10-21 22:04:57 -0700
years will use a similar pattern.
A new Zone Pacific/Bougainville, for the part of Papua New Guinea
- that plans to switch from +10 to +11 on 2014-12-28 at 02:00.
+ that plans to switch from UT +10 to +11 on 2014-12-28 at 02:00.
(Thanks to Kiley Walbom for the heads-up.)
Changes affecting time zone abbreviations
@@ -701,7 +701,7 @@ Release 2014i - 2014-10-21 22:04:57 -0700
to its more-traditional value MSK on 2014-10-26 at 01:00.
(Thanks to Alexander Bokovoy for the heads-up about Belarus.)
- The new abbreviation IDT stands for the pre-1976 use of +08 in
+ The new abbreviation IDT stands for the pre-1976 use of UT +08 in
Indochina, to distinguish it better from ICT (+07).
Changes affecting past time stamps
@@ -813,8 +813,8 @@ Release 2014g - 2014-08-28 12:31:23 -0700
Changes affecting future time stamps
- Turks & Caicos is switching from US eastern time to -04 year-round,
- modeled as a switch from EST/EDT to AST on 2014-11-02 at 02:00.
+ Turks & Caicos is switching from US eastern time to UT -04
+ year-round, modeled as a switch on 2014-11-02 at 02:00.
[As noted in 2014j, this switch was later delayed.]
Changes affecting past time stamps
@@ -997,7 +997,7 @@ Release 2014f - 2014-08-05 17:42:36 -0700
This change does not affect UTC offsets, only time zone abbreviations.
(Thanks to Rich Tibbett and many others.)
- Asia/Novokuznetsk shifts from NOVT to KRAT (remaining on +07)
+ Asia/Novokuznetsk shifts from NOVT to KRAT (remaining on UT +07)
effective 2014-10-26 at 02:00 local time.
The time zone abbreviation for Xinjiang Time (observed in Ürümqi)
@@ -1026,7 +1026,7 @@ Release 2014f - 2014-08-05 17:42:36 -0700
zones Asia/Harbin, Asia/Chongqing, and Asia/Kashgar have been
removed; backwards-compatibility links still work, albeit with
different behaviors for time stamps before May 1980. Asia/Urumqi's
- 1980 transition to +08 has been removed, so that it is now at
+ 1980 transition to UT +08 has been removed, so that it is now at
+06 and not +08. (Thanks to Luther Ma and to Alois Treindl;
Treindl sent helpful translations of two papers by Guo Qingsheng.)
@@ -1057,8 +1057,8 @@ Release 2014f - 2014-08-05 17:42:36 -0700
Europe/Helsinki's 1942 fall-back transition was 10-04 at 01:00, not
10-03 at 00:00. (Thanks to Konstantin Hyppönen.)
- Pacific/Pago_Pago has been changed from -11:30 to -11 for the period
- from 1911 to 1950.
+ Pacific/Pago_Pago has been changed from UT -11:30 to -11 for the
+ period from 1911 to 1950.
Pacific/Chatham has been changed to New Zealand standard time plus
45 minutes for the period before 1957, reflecting a 1956 remark in
@@ -1385,15 +1385,15 @@ Release 2013h - 2013-10-25 15:32:32 -0700
Changes affecting current and future time stamps:
- Libya has switched its time zone back to +02 without DST,
- instead of +01 with DST. (Thanks to Even Scharning.)
+ Libya has switched its UT offset back to +02 without DST, instead
+ of +01 with DST. (Thanks to Even Scharning.)
Western Sahara (Africa/El_Aaiun) uses Morocco's DST rules.
(Thanks to Gwillim Law.)
Changes affecting future time stamps:
- Acre and (we guess) western Amazonas will switch from -04 to -05
+ Acre and (we guess) western Amazonas will switch from UT -04 to -05
on 2013-11-10. This affects America/Rio_Branco and America/Eirunepe.
(Thanks to Steffen Thorsen.)
@@ -1480,7 +1480,7 @@ Release 2013f - 2013-09-24 23:37:36 -0700
Tocantins will very likely not observe DST starting this spring.
(Thanks to Steffen Thorsen.)
- Jordan will likely stay at +03 indefinitely, and will not fall
+ Jordan will likely stay at UT +03 indefinitely, and will not fall
back this fall.
Palestine will fall back at 00:00, not 01:00. (Thanks to Steffen Thorsen.)
@@ -1537,7 +1537,7 @@ Release 2013e - 2013-09-19 23:50:04 -0700
Benny Lin.) This affects Asia/Dili, Asia/Jakarta, Asia/Jayapura,
Asia/Makassar, and Asia/Pontianak.
- Use ART (-03, standard time), rather than WARST (also UTC-3, but
+ Use ART (UT -03, standard time), rather than WARST (also -03, but
daylight saving time) for San Luis, Argentina since 2009.
Changes affecting Godthåb time stamps after 2037 if version mismatch
@@ -1994,7 +1994,7 @@ Release 2012f - 2012-09-12 23:17:03 -0700
Release 2012e - 2012-08-02 20:44:55 -0700
- * australasia (Pacific/Fakaofo): Tokelau is +13, not +14.
+ * australasia (Pacific/Fakaofo): Tokelau is UT +13, not +14.
(Thanks to Steffen Thorsen.)
* Use a single version number for both code and data.
diff --git a/Theory b/Theory
index d8d3882..6d7342c 100644
@@ -323,7 +323,7 @@ Errors in the tz database arise from many sources:
* Sometimes historical timekeeping was specified more precisely
than what the tz database can handle. For example, from 1909 to
- 1937 Netherlands clocks were legally +00:19:32.13, but the tz
+ 1937 Netherlands clocks were legally UT +00:19:32.13, but the tz
database cannot represent the fractional second.
* Even when all the timestamp transitions recorded by the tz database
diff --git a/africa b/africa
index 43c8e23..d35aaa5 100644
@@ -464,7 +464,7 @@ Zone Africa/Monrovia -0:43:08 - LMT 1882
# From Paul Eggert (2013-10-25):
-# For now, assume they're reverting to the pre-2012 rules of permanent +02.
+# For now, assume they're reverting to the pre-2012 rules of permanent UT +02.
# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
Rule Libya 1951 only - Oct 14 2:00 1:00 S
diff --git a/antarctica b/antarctica
index f8b4bfb..e461fcf 100644
@@ -27,7 +27,7 @@
# previously sealers and scientific personnel wintered
# Margaret Turner reports
-# (1999-09-30) that they're UTC+5, with no DST;
+# (1999-09-30) that they're UT +05, with no DST;
# presumably this is when they have visitors.
# year-round bases
diff --git a/asia b/asia
index a935476..e285326 100644
@@ -380,7 +380,7 @@ Rule PRC 1987 1991 - Apr Sun>=10 0:00 1:00 D
# Lewiston (ME) Daily Sun (1939-05-29), p 17, said "Even the time is
# different - the occupied districts going by Tokyo time, an hour
# ahead of that prevailing in the rest of Shanghai." Guess that the
-# Xujiahui Observatory was under French control and stuck with +08.
+# Xujiahui Observatory was under French control and stuck with UT +08.
# In earlier versions of this file, China had many separate Zone entries, but
# this was based on what were apparently incorrect data in Shanks & Pottenger.
@@ -389,26 +389,26 @@ Rule PRC 1987 1991 - Apr Sun>=10 0:00 1:00 D
# Proposed in 1918 and theoretically in effect until 1949 (although in practice
# mainly observed in coastal areas), the five zones were:
-# Changbai Time ("Long-white Time", Long-white = Heilongjiang area) +08:30
+# Changbai Time ("Long-white Time", Long-white = Heilongjiang area) UT +08:30
# Asia/Harbin (currently a link to Asia/Shanghai)
# Heilongjiang (except Mohe county), Jilin
-# Zhongyuan Time ("Central plain Time") -08
+# Zhongyuan Time ("Central plain Time") UT +08
# most of China
# This currently represents most other zones as well,
# as apparently these regions have been the same since 1970.
# Milne gives 8:05:43.2 for Xujiahui Observatory time; round to nearest.
-# Guo says Shanghai switched to +08 "from the end of the 19th century".
+# Guo says Shanghai switched to UT +08 "from the end of the 19th century".
-# Long-shu Time (probably due to Long and Shu being two names of that area) +07
+# Long-shu Time (probably due to Long and Shu being two names of the area) UT +07
# Asia/Chongqing (currently a link to Asia/Shanghai)
# Guangxi, Guizhou, Hainan, Ningxia, Sichuan, Shaanxi, and Yunnan;
# most of Gansu; west Inner Mongolia; west Qinghai; and the Guangdong
# counties Deqing, Enping, Kaiping, Luoding, Taishan, Xinxing,
# Yangchun, Yangjiang, Yu'nan, and Yunfu.
-# Xin-zang Time ("Xinjiang-Tibet Time") +06
+# Xin-zang Time ("Xinjiang-Tibet Time") UT +06
# This currently represents Kunlun Time as well,
# as apparently the two regions have been the same since 1970.
@@ -421,7 +421,7 @@ Rule PRC 1987 1991 - Apr Sun>=10 0:00 1:00 D
# Shihezi, Changji, Yanqi, Heshuo, Tuokexun, Tulufan, Shanshan, Hami,
# Fukang, Kuitun, Kumukuli, Miquan, Qitai, and Turfan.
-# Kunlun Time +05:30
+# Kunlun Time UT +05:30
# Asia/Kashgar (currently a link to Asia/Urumqi)
# West Tibet, including Pulan, Aheqi, Shufu, Shule;
# West Xinjiang, including Aksu, Atushi, Yining, Hetian, Cele, Luopu, Nileke,
@@ -437,7 +437,7 @@ Rule PRC 1987 1991 - Apr Sun>=10 0:00 1:00 D
# On the other hand, ethnic Uyghurs, who make up about half the
# population of Xinjiang, typically use "Xinjiang time" which is two
-# hours behind Beijing time, or UTC +0600. The government of the Xinjiang
+# hours behind Beijing time, or UT +06. The government of the Xinjiang
# Uyghur Autonomous Region, (XAUR, or just Xinjiang for short) as well as
# local governments such as the Ürümqi city government use both times in
# publications, referring to what is popularly called Xinjiang time as
@@ -493,8 +493,8 @@ Rule PRC 1987 1991 - Apr Sun>=10 0:00 1:00 D
# having the same time as Beijing.
# From Paul Eggert (2014-06-30):
-# In the early days of the PRC, Tibet was given its own time zone (+06) but
-# this was withdrawn in 1959 and never reinstated; see Tubten Khétsun,
+# In the early days of the PRC, Tibet was given its own time zone (UT +06)
+# but this was withdrawn in 1959 and never reinstated; see Tubten Khétsun,
# Memories of life in Lhasa under Chinese Rule, Columbia U Press, ISBN
# 978-0231142861 (2008), translator's introduction by Matthew Akester, p x.
# As this is before our 1970 cutoff, Tibet doesn't need a separate zone.
@@ -508,7 +508,7 @@ Rule PRC 1987 1991 - Apr Sun>=10 0:00 1:00 D
# Republics, the Soviet Union, the Kuomintang, and the People's Republic of
# China, and tracking down all these organizations' timekeeping rules would be
# quite a trick. Approximate this lost history by a transition from LMT to
-# +06 at the start of 1928, the year of accession of the warlord Jin Shuren,
+# UT +06 at the start of 1928, the year of accession of the warlord Jin Shuren,
# which happens to be the date given by Shanks & Pottenger (no doubt as a
# guess) as the transition from LMT. Ignore the usage of +08 before
# 1986-02-01 under the theory that the transition date to +08 is unknown and
@@ -718,7 +718,7 @@ Zone Asia/Hong_Kong 7:36:42 - LMT 1904 Oct 30
# be found from historical government announcement database.
# From Paul Eggert (2014-07-03):
-# As per Yu-Cheng Chuang, say that Taiwan was at +09 from 1937-10-01
+# As per Yu-Cheng Chuang, say that Taiwan was at UT +09 from 1937-10-01
# until 1945-09-21 at 01:00, overriding Shanks & Pottenger.
# Likewise, use Yu-Cheng Chuang's data for DST in Taiwan.
@@ -917,7 +917,7 @@ Zone Asia/Kolkata 5:53:28 - LMT 1880 # Kolkata
# These would be the earliest possible times for a change.
# Régimes horaires pour le monde entier, by Henri Le Corre, (Éditions
# Traditionnelles, 1987, Paris) says that Java and Madura switched
-# from +09 to +07:30 on 1945-09-23, and gives 1944-09-01 for Jayapura
+# from UT +09 to +07:30 on 1945-09-23, and gives 1944-09-01 for Jayapura
# (Hollandia). For now, assume all Indonesian locations other than Jayapura
# switched on 1945-09-23.
@@ -928,7 +928,7 @@ Zone Asia/Kolkata 5:53:28 - LMT 1880 # Kolkata
# summary published by the Time and Frequency Laboratory of the
# Research Center for Calibration, Instrumentation and Metrology,
# Indonesia, <http://time.kim.lipi.go.id/time-eng.php> (2006-09-29).
-# The abbreviations are:
+# The time zone abbreviations and UT offsets are:
# WIB - +07 - Waktu Indonesia Barat (Indonesia western time)
# WITA - +08 - Waktu Indonesia Tengah (Indonesia central time)
@@ -2041,7 +2041,7 @@ Zone Indian/Maldives 4:54:00 - LMT 1880 # Male
# Bill Bonnet (2005-05-19) reports that the US Embassy in Ulaanbaatar says
# there is only one time zone and that DST is observed, citing Microsoft
# Windows XP as the source. Risto Nykänen (2005-05-16) reports that
-# travelmongolia.org says there are two time zones (+07, +08) with no DST.
+# travelmongolia.org says there are two time zones (UT +07, +08) with no DST.
# Oscar van Vlijmen (2005-05-20) reports that the Mongolian Embassy in
# Washington, DC says there are two time zones, with DST observed.
# He also found
@@ -2677,7 +2677,7 @@ Link Asia/Qatar Asia/Bahrain
# earlier date.
# Shanks & Pottenger also state that until 1968-05-01 Saudi Arabia had two
-# time zones; the other zone, at +04, was in the far eastern part of
+# time zones; the other zone, at UT +04, was in the far eastern part of
# the country. Ignore this, as it's before our 1970 cutoff.
# Zone NAME GMTOFF RULES FORMAT [UNTIL]
diff --git a/australasia b/australasia
index fe77d07..f49df1d 100644
@@ -545,7 +545,7 @@ Zone Pacific/Port_Moresby 9:48:40 - LMT 1880
# Base the Bougainville entry on the Arawa-Kieta region, which appears to have
# the most people even though it was devastated in the Bougainville Civil War.
-# Although Shanks gives 1942-03-15 / 1943-11-01 for +09, these dates
+# Although Shanks gives 1942-03-15 / 1943-11-01 for UT +09, these dates
# are apparently rough guesswork from the starts of military campaigns.
# The World War II entries below are instead based on Arawa-Kieta.
# The Japanese occupied Kieta in July 1942,
@@ -553,7 +553,7 @@ Zone Pacific/Port_Moresby 9:48:40 - LMT 1880
# and seem to have controlled it until their 1945-08-21 surrender.
-# The Autonomous Region of Bougainville switched from +10 to +11
+# The Autonomous Region of Bougainville switched from UT +10 to +11
# on 2014-12-28 at 02:00. They call +11 "Bougainville Standard Time";
# abbreviate this as BST. See:
@@ -620,7 +620,7 @@ Link Pacific/Pago_Pago Pacific/Midway # in US minor outlying islands
# From Paul Eggert (2014-06-27):
# The International Date Line Act 2011
-# changed Samoa from -11 to +13, effective "12 o'clock midnight, on
+# changed Samoa from UT -11 to +13, effective "12 o'clock midnight, on
# Thursday 29th December 2011". The International Date Line was adjusted
@@ -715,7 +715,7 @@ Zone Pacific/Funafuti 11:56:52 - LMT 1901
# 1886-1891; Baker was similar but exact dates are not known.
# Inhabited by civilians 1935-1942; U.S. military bases 1943-1944;
# uninhabited thereafter.
-# Howland observed Hawaii Standard Time (-10:30) in 1937;
+# Howland observed Hawaii Standard Time (UT -10:30) in 1937;
# see page 206 of Elgen M. Long and Marie K. Long,
# Amelia Earhart: the Mystery Solved, Simon & Schuster (2000).
# So most likely Howland and Baker observed Hawaii Time from 1935
@@ -1473,7 +1473,7 @@ Zone Pacific/Wallis 12:15:20 - LMT 1901
# Zealand time. I understand that is the time they keep locally, anyhow."
# For now, assume this practice goes back to the introduction of standard time
# in New Zealand, as this would make Chatham Islands time almost exactly match
-# LMT back when New Zealand was at +11:30; also, assume Chatham Islands did
+# LMT back when New Zealand was at UT +11:30; also, assume Chatham Islands did
# not observe New Zealand's prewar DST.
@@ -1529,7 +1529,7 @@ Zone Pacific/Wallis 12:15:20 - LMT 1901
# For now, we assume the Ladrones switched at the same time as the Philippines;
# see Asia/Manila.
-# US Public Law 106-564 (2000-12-23) made +10 the official standard time,
+# US Public Law 106-564 (2000-12-23) made UT +10 the official standard time,
# under the name "Chamorro Standard Time". There is no official abbreviation,
# but Congressman Robert A. Underwood, author of the bill that became law,
# wrote in a press release (2000-12-27) that he will seek the use of "ChST".
@@ -1541,14 +1541,14 @@ Zone Pacific/Wallis 12:15:20 - LMT 1901
# "I am certain, having lived there for the past decade, that 'Truk'
# (now properly known as Chuuk) ... is in the time zone GMT+10."
-# Shanks & Pottenger write that Truk switched from +10 to +11
+# Shanks & Pottenger write that Truk switched from UT +10 to +11
# on 1978-10-01; ignore this for now.
# From Paul Eggert (1999-10-29):
# The Federated States of Micronesia Visitors Board writes in
# The Federated States of Micronesia - Visitor Information (1999-01-26)
-# that Truk and Yap are +10, and Ponape and Kosrae are +11.
+# that Truk and Yap are UT +10, and Ponape and Kosrae are +11.
# We don't know when Kosrae switched from +12; assume January 1 for now.
@@ -1615,7 +1615,7 @@ Zone Pacific/Wallis 12:15:20 - LMT 1901
# ordaining - by a masterpiece of diplomatic flattery - that
# the Fourth of July should be celebrated twice in that year."
-# Although Shanks & Pottenger says they both switched to -11:30
+# Although Shanks & Pottenger says they both switched to UT -11:30
# in 1911, and to -11 in 1950. many earlier sources give -11
# for American Samoa, e.g., the US National Bureau of Standards
# circular "Standard Time Throughout the World", 1932.
diff --git a/backzone b/backzone
index 27a5472..4a5085f 100644
@@ -194,7 +194,7 @@ Zone Africa/Lusaka 1:53:08 - LMT 1903 Mar
# Equatorial Guinea
-# Although Shanks says that Malabo switched from +00 to +01 on 1963-12-15,
+# Although Shanks says that Malabo switched from UT +00 to +01 on 1963-12-15,
# a Google Books search says that London Calling, Issues 432-465 (1948), p 19,
# says that Spanish Guinea was at +01 back then. The Shanks data entries
# are most likely wrong, but we have nothing better; use them here for now.
@@ -479,13 +479,13 @@ Zone Asia/Muscat 3:54:24 - LMT 1920
# From Paul Eggert (2014-08-11), after a heads-up from Stephen Colebourne:
# According to a Portuguese decree (1911-05-26)
-# Portuguese India switched to +05 on 1912-01-01.
+# Portuguese India switched to UT +05 on 1912-01-01.
#Zone Asia/Panaji [not enough info to complete]
# From Paul Eggert (2014-10-11):
# See Asia/Ho_Chi_Minh for the source for most of this data. Also, guess
-# (1) Cambodia reverted to +07 on 1945-09-02, when Vietnam did, and
+# (1) Cambodia reverted to UT +07 on 1945-09-02, when Vietnam did, and
# (2) they also reverted to +07 on 1953-11-09, the date of independence.
# These guesses are probably wrong but they're better than guessing no
# transitions there.
@@ -506,7 +506,7 @@ Zone Asia/Tel_Aviv 2:19:04 - LMT 1880
# From Paul Eggert (2014-10-11):
# See Asia/Ho_Chi_Minh for the source for most of this data.
-# Trần's book says that Laos reverted to +07 on 1955-04-15.
+# Trần's book says that Laos reverted to UT +07 on 1955-04-15.
# Also, guess that Laos reverted to +07 on 1945-09-02, when Vietnam did;
# this is probably wrong but it's better than guessing no transition.
Zone Asia/Vientiane 6:50:24 - LMT 1906 Jul 1
diff --git a/europe b/europe
index 3a1f9db..21d3a71 100644
@@ -1309,7 +1309,7 @@ Zone Europe/Paris 0:09:21 - LMT 1891 Mar 15 0:01
# says that Bersarin issued an order to use Moscow time on May 20.
# However, Moscow did not observe daylight saving in 1945, so
-# this was equivalent to +03, not +04.
+# this was equivalent to UT +03, not +04.
# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
diff --git a/northamerica b/northamerica
index 0c069bb..0bafb00 100644
@@ -3312,7 +3312,7 @@ Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre
# indicating that the normal ET rules are followed.
# From Paul Eggert (2014-08-19):
-# The 2014-08-13 Cabinet meeting decided to stay on -04 year-round. See:
+# The 2014-08-13 Cabinet meeting decided to stay on UT -04 year-round. See:
# Model this as a switch from EST/EDT to AST ...
# From Chris Walton (2014-11-04):
More information about the tz