[1] MMT is used all year round, as Myanmar does not observe daylight saving time.
Each region kept its own local mean time, according to the Burmese calendar rules: sunrise, noon, sunset and midnight.
Although the calendar consists of time units down to the millisecond level, the popular usage never extended beyond baho and at most nayi measurements; a gong was struck every nayi while a drum (စည်) and a large bell (ခေါင်းလောင်း) were struck to mark every baho.
(The country's first rail service, between Rangoon and Prome (Pyay), began on 2 May 1877,[9] and the non-authoritative IANA time zone database says RMT was introduced in 1880.
[11][13] Although the rest of the country came to adopt BST, RMT continued to be used in the city of Rangoon at least to 1927.