The Armenian calendar is based on an invariant year length of 365 days.
In A.D. 352, tables compiled by Andreas of Byzantium were introduced in Armenia to determine the religious holidays.
Another prefix is Թ.Հ., standing for t’vin Hayocʿ (թուին Հայոց "in the Armenian year").
There are different systems for transliterating the names; the forms below are transliterated according to the Hübschmann-Meillet-Benveniste system: The Armenian calendar gives the days of the month names instead of numbering them – something also found in the Avestan calendars.
Non-working days include: Victory Day : 9 May (World War II) was a holiday throughout the USSR and is still an official holiday in Armenia.