Henry Ivy is not on the time zone mailing list; direct replies appropriately. --ado -----Original Message----- From: IVY,HENRY (HP-Roseville,ex1) [mailto:henry_ivy@am.exch.hp.com] Sent: Monday, April 01, 2002 9:15 PM To: 'tz@elsie.nci.nih.gov' Cc: VEGA,HORACIO (HP-Mexico,ex1); GRIMM,GREG (HP-Roseville,ex1) Subject: Daylight Savings Time in Mexico Dear Sirs; I work for Hewlett-Packard in Roseville, CA, USA. One of my assignments is to maintain daylight savings time schedules in special databases for world wide global support. I admire your work. I look forward to any comments that you may have about the following information. Horacio Vega works for HP in Mexico. He brought the following decree to my attention. His Spanish is better than mine. He has told me that Mexico City will use daylight savings time, along with most of Mexico. http://www.conae.gob.mx/ahorro/horaver2001_m1_2002.html#decreto I started with the tzdata2002b version of the data. The rules for Mexico Daylight Savings Time should have the 2001 rules commented out, and the previous two lines reset to run to max. The time zone rules for America/Mexico_City should have the last line commented out, and the previous line reset to not expire. The time zone rules for America/Tijuana should have the last line commented out, and the previous line reset to not expire. --------------- # 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 Rule Mexico 1943 only - Dec 16 0:00 1:00 W Rule Mexico 1944 only - May 1 0:00 0 S Rule Mexico 1950 only - Feb 12 0:00 1:00 D Rule Mexico 1950 only - Jul 30 0:00 0 S Rule Mexico 1996 max - Apr Sun>=1 2:00 1:00 D Rule Mexico 1996 max - Oct lastSun 2:00 0 S # Rule Mexico 2001 max - May Sun>=1 2:00 1:00 D # Rule Mexico 2001 max - Sep lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] # Quintana Roo 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 # Campeche, Yucatan 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, Durango, Nuevo Leon, Tamaulipas Zone America/Monterrey -6:41:16 - LMT 1921 Dec 31 23:18:44 -6:00 - CST 1988 -6:00 US C%sT 1989 -6:00 Mexico C%sT # Central Mexico Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 0:23:24 -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 -7:00 - MST 1932 Apr 1 -6:00 Mexico C%sT # -6:00 - CST # Chihuahua Zone America/Chihuahua -7:04:20 - LMT 1921 Dec 31 23:55:40 -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 -7:00 - MST 1932 Apr 1 -6:00 - CST 1996 -6:00 Mexico C%sT 1998 -6:00 - CST 1998 Apr Sun>=1 3:00 -7:00 Mexico M%sT # Sonora Zone America/Hermosillo -7:23:52 - LMT 1921 Dec 31 23:36:08 -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 -7:00 - MST 1932 Apr 1 -6:00 - CST 1942 Apr 24 -7:00 - MST 1949 Jan 14 -8:00 - PST 1970 -7:00 Mexico M%sT 1999 -7:00 - MST # Baja California Sur, Nayarit, Sinaloa Zone America/Mazatlan -7:05:40 - LMT 1921 Dec 31 23:54:20 -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 -7:00 - MST 1932 Apr 1 -6:00 - CST 1942 Apr 24 -7:00 - MST 1949 Jan 14 -8:00 - PST 1970 -7:00 Mexico M%sT # Baja California Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 0:11:56 -7:00 - MST 1924 -8:00 - PST 1927 Jun 10 23:00 -7:00 - MST 1930 Nov 15 -8:00 - PST 1931 Apr 1 -8:00 1:00 PDT 1931 Sep 30 -8:00 - PST 1942 Apr 24 -8:00 1:00 PWT 1945 Nov 12 -8:00 - PST 1948 Apr 5 -8:00 1:00 PDT 1949 Jan 14 -8:00 - PST 1954 -8:00 CA P%sT 1961 -8:00 - PST 1976 -8:00 US P%sT 1996 -8:00 Mexico P%sT # -8:00 US P%sT # From Paul Eggert (2001-03-05): # Formerly there was an America/Ensenada zone, which differed from # America/Tijuana only in that it did not observe DST from 1976 # through 1995. This was as per Shanks. However, Guy Harris reports # that the 1987 OAG says "Only Ensenada, Mexicale, San Felipe and # Tijuana observe DST," which contradicts Shanks but does imply that # DST-observance was a town-by-town matter back then. This concerns # data after 1970 so most likely there should be at least one Zone # other than America/Tijuana for Baja, but it's not clear yet what its # name or contents should be. # # Revillagigedo Is # no information ############################################################################ ### --------------- Regards, Hank Ivy | Henry (Hank) B. Ivy PHONE : (916)785-1392 | | FAX : (916)785-9238 | | ecardfile : https://ecardfile.com/id/hank_ivy | | Hewlett-Packard Company USENET: hivy@rosemail.rose.hp.com | | 8000 Foothills Boulevard, MS 5617 | | Roseville, California 95747-5617 |