The Kingdom of Saudi Arabia has Used the lunar-based Hijri calendar since it was founded in 1932. Recently The country switched to the solar-based Gregorian calendar for paying public sector staff on 1 October. The Islamic lunar calendar is made up of 12
months, every 29 or 30 days long depending on the sighting of the moon. With the Lunar Calendar The year usually 354 days long – 11 days shorter than its Western equivalent.
For This Reason, Saudi Arabia has switched to the “Western” Gregorian calendar to pay its civil servants in one of a number of financial reforms announced by the Council of Ministers.