from the first Sunday in April to the last Sunday in October.
Example: Pacific Standard Time is PST (GMT-8)
Pacific Daylight Time is PDT (GMT-7)
Some locations do not observe Daylight Savings (AZ, HI, IN, SK)
Daylight Savings Time in the World (1996)
Daylight Savings Time is adopted by law or decree separately in each country of the world. Accurate information is very difficult to come by, and various sources differ considerably on the matter.
The start/stop date is indicated as a rule (e.g. [Sun>=15]-Mar which means the third Sunday in March), if a rule applies. Also, exact dates for 1996 are given. The time change is usually accomplished in the early hours of the morning of the date given.