Year a leap year there are 366 days. A leap year occurs every fourth year, or leap year, during which a leap day is intercalated into the month of February. The name "Leap Day" is applied to the added day. The Revised Julian calendar, proposed in 1923 and used in some Eastern Orthodox Churches, has 218 leap years every 900 years, for the average (mean) year length of days, close to the length of the mean tropical year, days (relative error of 9·10). In the year 2800 CE, the Gregorian and Revised Julian calendars will begin to differ by one calendar
Solar Hijri calendar calendar of 365 days for three consecutive years plus an extra day in the next year, save for exceptions to the latter in three out of every four centenaries). The start of the year and its number of days remain fixed to one of the two equinoxes, the astronomically important days which have the same duration of the sun. It results in less variability of all celestial bodies comparing a specific calendar date from one year to others. Each of the twelve months corresponds with a zodiac sign. The first six months have 31 days, the next five have 30