Oct 21, 1979, 3:30 am
| Start DST: | Sunday, April 22, 1973 — 1 hour forward |
|---|---|
| End DST: | Sunday, October 21, 1973 — 1 hour backward |
Apr 22
Forward 1 hour
Apr 22, 1973 - Daylight Saving Time Started
When local standard time was about to reach
Sunday, April 22, 1973, 3:30:00 am clocks were turned forward 1 hour to
Sunday, April 22, 1973, 4:30:00 am local daylight time instead.
Sunrise and sunset were about 1 hour later on Apr 22, 1973 than the day before. There was more light in the evening and less light in the morning.
Also called Spring Forward, Summer Time, and Daylight Savings Time.
Oct 21
Back 1 hour
Oct 21, 1973 - Daylight Saving Time Ended
When local daylight time was about to reach
Sunday, October 21, 1973, 3:30:00 am clocks were turned backward 1 hour to
Sunday, October 21, 1973, 2:30:00 am local standard time instead.
Sunrise and sunset were about 1 hour earlier on Oct 21, 1973 than the day before. There was more light in the morning and less light in the evening.
Also called Fall Back and Winter Time.
Dec 30
Forward 1 hour
Dec 30, 1973 - Daylight Saving Time Started
When local standard time was about to reach
Sunday, December 30, 1973, 3:30:00 am clocks were turned forward 1 hour to
Sunday, December 30, 1973, 4:30:00 am local daylight time instead.
Sunrise and sunset were about 1 hour later on Dec 30, 1973 than the day before. There was more light in the evening and less light in the morning.
Also called Spring Forward, Summer Time, and Daylight Savings Time.
Daylight Saving Time in Other Years
DST changes do not necessarily occur on the same date every year.
| Year | DST Start (Clock Forward) | DST End (Clock Backward) |
|---|---|---|
| 1970 | Sunday, April 19, 3:30 am | Sunday, October 18, 3:30 am |
| 1971 | Sunday, April 18, 3:30 am | Sunday, October 17, 3:30 am |
| 1972 | Sunday, April 16, 3:30 am | Sunday, October 22, 3:30 am |
| * 1973 | Sunday, April 22, 3:30 am | Sunday, October 21, 3:30 am |
| 1974 | No DST Start | Sunday, October 20, 3:30 am |
| 1975 | Sunday, April 20, 3:30 am | Sunday, October 19, 3:30 am |
| 1976 | Sunday, April 18, 3:30 am | Sunday, October 17, 3:30 am |
| 1977 — 1978 | DST not observed | |
| 1979 | Sunday, May 13, 3:30 am | Sunday, October 21, 3:30 am |
| All times are local for 22°14'52"N, 114°12'10"E. * All or part of this period was on double DST. | ||
Data for the years before 1970 is not available for 22°14'52"N, 114°12'10"E, however, we have earlier time zone history for Hong Kong available.
Detailed time zone and clock changes in 22°14'52"N, 114°12'10"E