Asia/Chongqing

Time zone identifier: Asia/Chongqing

Current civil offset: +08:00 (CST)

Current DST state: Observing Standard Time

First standard time adoption: Adopted on 1900-12-31

Local Mean Time (LMT): +08:05:43 based on geographic meridian

Total recorded transitions: 29 transitions across 3 distinct offsets

Aliases (Link targets): Asia/Chungking

Historical Offset Step Chart (1880 to Present)

Text summary: Asia/Chongqing shifted between 3 distinct offsets from 1900-12-31 through the modern era.

Complete Transition History (29 Transitions)

UTC Instant	Local Wall Time	Shift	Abbreviation	DST	Effect
`1900-12-31T15:54:17Z`	`1900-12-31 23:54:17`	+08:05:43 → +08:00	`CST`	No	overlap
`1919-04-12T16:00:00Z`	`1919-04-13 01:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1919-09-30T15:00:00Z`	`1919-09-30 23:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1940-05-31T16:00:00Z`	`1940-06-01 01:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1940-10-12T15:00:00Z`	`1940-10-12 23:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1941-03-14T16:00:00Z`	`1941-03-15 01:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1941-11-01T15:00:00Z`	`1941-11-01 23:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1942-01-30T16:00:00Z`	`1942-01-31 01:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1945-09-01T15:00:00Z`	`1945-09-01 23:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1946-05-14T16:00:00Z`	`1946-05-15 01:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1946-09-30T15:00:00Z`	`1946-09-30 23:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1947-04-14T16:00:00Z`	`1947-04-15 01:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1947-10-31T15:00:00Z`	`1947-10-31 23:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1948-04-30T16:00:00Z`	`1948-05-01 01:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1948-09-30T15:00:00Z`	`1948-09-30 23:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1949-04-30T16:00:00Z`	`1949-05-01 01:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1949-05-27T15:00:00Z`	`1949-05-27 23:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1986-05-03T18:00:00Z`	`1986-05-04 03:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1986-09-13T17:00:00Z`	`1986-09-14 01:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1987-04-11T18:00:00Z`	`1987-04-12 03:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1987-09-12T17:00:00Z`	`1987-09-13 01:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1988-04-16T18:00:00Z`	`1988-04-17 03:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1988-09-10T17:00:00Z`	`1988-09-11 01:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1989-04-15T18:00:00Z`	`1989-04-16 03:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1989-09-16T17:00:00Z`	`1989-09-17 01:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1990-04-14T18:00:00Z`	`1990-04-15 03:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1990-09-15T17:00:00Z`	`1990-09-16 01:00:00`	+09:00 → +08:00	`CST`	No	overlap
`1991-04-13T18:00:00Z`	`1991-04-14 03:00:00`	+08:00 → +09:00	`CDT`	Yes	gap
`1991-09-14T17:00:00Z`	`1991-09-15 01:00:00`	+09:00 → +08:00	`CST`	No	overlap

Notes from the Maintainers

Source: backzone (Lines 1007 to 1027)

India

From Paul Eggert (2014-09-06):
The 1876 Report of the Secretary of the [US] Navy, p 305 says that Madras
civil time was 5:20:57.3.

From Paul Eggert (2014-08-21):
In tomorrow's The Hindu, Nitya Menon reports that India had two civil time
zones starting in 1884, one in Bombay and one in Calcutta, and that railways
used a third time zone based on Madras time (80° 18' 30" E).  Also,
in 1881 Bombay briefly switched to Madras time, but switched back.  See:
http://www.thehindu.com/news/cities/chennai/madras-375-when-madras-clocked-the-time/article6339393.ece
Zone	  Asia/Chennai  [not enough info to complete]

China
Long-shu Time (probably due to Long and Shu being two names of that area)
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.

Attributed Statements:

Paul Eggert (2014-09-06):

The 1876 Report of the Secretary of the [US] Navy, p 305 says that Madras civil time was 5:20:57.3.

Paul Eggert (2014-08-21):

In tomorrow's The Hindu, Nitya Menon reports that India had two civil time zones starting in 1884, one in Bombay and one in Calcutta, and that railways used a third time zone based on Madras time (80° 18' 30" E). Also, in 1881 Bombay briefly switched to Madras time, but switched back. See: http://www.thehindu.com/news/cities/chennai/madras-375-when-madras-clocked-the-time/article6339393.ece Zone Asia/Chennai [not enough info to complete] China Long-shu Time (probably due to Long and Shu being two names of that area) 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.

Years on Record

Methodology Note: The 1970 Rule

tzdb guarantees accuracy for timestamps from 1970 onwards. Transitions prior to 1970 represent best-effort historical reconstructions.