FW: Chinese timezones do not observe DST
Since sending this message, Alexandru Pulbere has been added to the time zone mailing list. --ado _____ From: Pulbere, Alexandru [mailto:Alexandru.Pulbere@cognos.com] Sent: Thursday, August 05, 2004 6:56 PM To: tz@lecserver.nci.nih.gov Subject: Chinese timezones do not observe DST I noticed that the timezone description for chinese timezones use DST. Aparently the chinese governament stopped using DST in 1992. To fix the problem I changed my copy asia file and regenerated ICU4J resources (my copy). # China # From Guy Harris: # People's Republic of China. Yes, they really have only one time zone. # From Bob Devine (1988-01-28): # No they don't. See TIME mag, 1986-02-17 p.52. Even though # China is across 4 physical time zones, before Feb 1, 1986 only the # Peking (Bejing) time zone was recognized. Since that date, China # has two of 'em -- Peking's and Urumqi (named after the capital of # the Xinjiang Uyghur Autonomous Region). I don't know about DST for it. # # . . .I just deleted the DST table and this editor makes it too # painful to suck in another copy.. So, here is what I have for # DST start/end dates for Peking's time zone (info from AP): # # 1986 May 4 - Sept 14 # 1987 mid-April - ?? # From U. S. Naval Observatory (1989-01-19): # CHINA 8 H AHEAD OF UTC ALL OF CHINA, INCL TAIWAN # CHINA 9 H AHEAD OF UTC APR 17 - SEP 10 # From Paul Eggert <eggert@twinsun.com> (1995-12-19): # Shanks writes that China has had a single time zone since 1980 May 1, # observing summer DST from 1986 through 1991; this contradicts Devine's # note about Time magazine, though apparently _something_ happened in 1986. # Go with Shanks for now. I made up names for the other pre-1980 time zones. # From Shanks: # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Shang 1940 only - Jun 3 0:00 1:00 D Rule Shang 1940 1941 - Oct 1 0:00 0 S Rule Shang 1941 only - Mar 16 0:00 1:00 D Rule PRC 1949 only - Jan 1 0:00 0 S Rule PRC 1986 only - May 4 0:00 1:00 D Rule PRC 1986 1991 - Sep Sun>=11 0:00 0 S Rule PRC 1987 1991 - Apr Sun>=10 0:00 1:00 D # # Zone NAME GMTOFF RULES FORMAT [UNTIL] # # From Anthony Fok (2001-12-20): # BTW, I did some research on-line and found some info regarding these five # historic timezones from some Taiwan websites. And yes, there are official # Chinese names for these locales (before 1949): # Changbai Time ("Long-white Time", Long-white = Heilongjiang area) Zone Asia/Harbin 8:26:44 - LMT 1928 # or Haerbin 8:30 - CHAT 1932 Mar # Changbai Time 8:00 - CST 1940 9:00 - CHAT 1966 May 8:30 - CHAT 1980 May 8:00 PRC C%sT 1992 8:00 - CST # Zhongyuan Time ("Central plain Time") Zone Asia/Shanghai 8:05:52 - LMT 1928 8:00 Shang C%sT 1949 8:00 PRC C%sT 1992 8:00 - CST # Long-shu Time (probably due to Long and Shu being two names of that area) Zone Asia/Chongqing 7:06:20 - LMT 1928 # or Chungking 7:00 - LONT 1980 May # Long-shu Time 8:00 PRC C%sT 1992 8:00 - CST # Xin-zang Time ("Xinjiang-Tibet Time") Zone Asia/Urumqi 5:50:20 - LMT 1928 # or Urumchi 6:00 - URUT 1980 May # Urumqi Time 8:00 PRC C%sT 1992 8:00 - CST # Kunlun Time Zone Asia/Kashgar 5:03:56 - LMT 1928 # or Kashi or Kaxgar 5:30 - KAST 1940 # Kashgar Time 5:00 - KAST 1980 May 8:00 PRC C%sT 1992 8:00 - CST # Hong Kong (Xianggang) # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule HK 1946 only - Apr 20 3:30 1:00 S Rule HK 1946 only - Dec 1 3:30 0 - Rule HK 1947 only - Apr 13 3:30 1:00 S Rule HK 1947 only - Dec 30 3:30 0 - Rule HK 1948 only - May 2 3:30 1:00 S Rule HK 1948 1952 - Oct lastSun 3:30 0 - Rule HK 1949 1953 - Apr Sun>=1 3:30 1:00 S Rule HK 1953 only - Nov 1 3:30 0 - Rule HK 1954 1964 - Mar Sun>=18 3:30 1:00 S Rule HK 1954 only - Oct 31 3:30 0 - Rule HK 1955 1964 - Nov Sun>=1 3:30 0 - Rule HK 1965 1977 - Apr Sun>=16 3:30 1:00 S Rule HK 1965 1977 - Oct Sun>=16 3:30 0 - Rule HK 1979 1980 - May Sun>=8 3:30 1:00 S Rule HK 1979 1980 - Oct Sun>=16 3:30 0 - # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Hong_Kong 7:36:36 - LMT 1904 Oct 30 8:00 HK HK%sT 2002 8:00 - CST ############################################################################ ### # Taiwan # Shanks writes that Taiwan observed DST during 1945, when it # was still controlled by Japan. This is hard to believe, but we don't # have any other information. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Taiwan 1945 1951 - May 1 0:00 1:00 D Rule Taiwan 1945 1951 - Oct 1 0:00 0 S Rule Taiwan 1952 only - Mar 1 0:00 1:00 D Rule Taiwan 1952 1954 - Nov 1 0:00 0 S Rule Taiwan 1953 1959 - Apr 1 0:00 1:00 D Rule Taiwan 1955 1961 - Oct 1 0:00 0 S Rule Taiwan 1960 1961 - Jun 1 0:00 1:00 D Rule Taiwan 1974 1975 - Apr 1 0:00 1:00 D Rule Taiwan 1974 1975 - Oct 1 0:00 0 S Rule Taiwan 1980 only - Jun 30 0:00 1:00 D Rule Taiwan 1980 only - Sep 30 0:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Taipei 8:06:00 - LMT 1896 # or Taibei or T'ai-pei 8:00 Taiwan C%sT 1992 8:00 - CST # Macau (Macao, Aomen) # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Macau 1961 1962 - Mar Sun>=16 3:30 1:00 S Rule Macau 1961 1964 - Nov Sun>=1 3:30 0 - Rule Macau 1963 only - Mar Sun>=16 0:00 1:00 S Rule Macau 1964 only - Mar Sun>=16 3:30 1:00 S Rule Macau 1965 only - Mar Sun>=16 0:00 1:00 S Rule Macau 1965 only - Oct 31 0:00 0 - Rule Macau 1966 1971 - Apr Sun>=16 3:30 1:00 S Rule Macau 1966 1971 - Oct Sun>=16 3:30 0 - Rule Macau 1972 1974 - Apr Sun>=15 0:00 1:00 S Rule Macau 1972 1973 - Oct Sun>=15 0:00 0 - Rule Macau 1974 1977 - Oct Sun>=15 3:30 0 - Rule Macau 1975 1977 - Apr Sun>=15 3:30 1:00 S Rule Macau 1978 1980 - Apr Sun>=15 0:00 1:00 S Rule Macau 1978 1980 - Oct Sun>=15 0:00 0 - # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Macau 7:34:20 - LMT 1912 8:00 Macau MO%sT 1999 Dec 20 # return to China 8:00 - CST This message may contain privileged and/or confidential information. 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From: Pulbere, Alexandru [mailto:Alexandru.Pulbere@cognos.com] Sent: Thursday, August 05, 2004 6:56 PM
(my copy).
That change isn't necessary, since the Rule lines say that China last used DST in 1991, so zic can deduce that no transitions occurred after 1991. For example, here's what I get if I run the command "zdump -v Asia/Shanghai | tail -n 6" without your change: Asia/Shanghai Sat Apr 13 15:59:59 1991 UTC = Sat Apr 13 23:59:59 1991 CST isdst=0 Asia/Shanghai Sat Apr 13 16:00:00 1991 UTC = Sun Apr 14 01:00:00 1991 CDT isdst=1 Asia/Shanghai Sat Sep 14 14:59:59 1991 UTC = Sat Sep 14 23:59:59 1991 CDT isdst=1 Asia/Shanghai Sat Sep 14 15:00:00 1991 UTC = Sat Sep 14 23:00:00 1991 CST isdst=0 Asia/Shanghai Mon Jan 18 03:14:07 2038 UTC = Mon Jan 18 11:14:07 2038 CST isdst=0 Asia/Shanghai Tue Jan 19 03:14:07 2038 UTC = Tue Jan 19 11:14:07 2038 CST isdst=0
participants (2)
-
Olson, Arthur David (NIH/NCI) -
Paul Eggert