Kurdish calendar by a leap year every fourth year. It starts with the exact first day of spring according to the Gregorian calendar (March 20 or 21). Like the Gregorian system, the Kurdish calendar divides the year into four seasons: Buhar, Tawistan or Hawín, Payiz and Zimistan. It divides the year into 12 months, each month into four weeks and every week into seven days. In the Kurdish calendar the first six months (comprising spring and summer) are each 31 days long, while the next five months (in fall and winter) are 30 days each. The last winter month, the 12th month
Adoption of the Gregorian calendar days to be omitted from the calendar. Philip II of Spain decreed the change from the Julian to the Gregorian calendar, which affected much of Roman Catholic Europe, as Philip was at the time ruler over Spain and Portugal as well as much of Italy. In these territories, as well as in the Polish–Lithuanian Commonwealth (ruled by Anna Jagiellon) and in the Papal States, the new calendar was implemented on the date specified by the bull, with Julian Thursday, 4 October 1582, being followed by Gregorian Friday, 15 October 1582; the Spanish and Portuguese colonies followed somewhat later "de facto"