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
Day-year principle Therefore, Baha'is understand the 1260-day prophecies in both Daniel and in the Book of Revelation as referring to the year 1260 of the Islamic calendar which corresponds to the year 1844 AD, the year the Báb pronounced himself to be a Messenger of God and the year that the Baha'i Faith began. Baha'is have also applied the Day-Year principle to Rev. 9:15 which states, "And the four angels were loosed, which were prepared for an hour, and a day, and a month, and a year, for to slay the third part of men." The slaying of "the third part of