Leap year before 1, but only if the year is expressed with astronomical year numbering. It is not valid for the BC or BCE notation. The algorithm is not necessarily valid for years in the Julian calendar, such as years before 1752 in the British Empire. The year 1700 was a leap year in the Julian calendar, but not in the Gregorian calendar. February 29 is a date that usually occurs every four years, and is called leap day. This day is added to the calendar in leap years as a corrective measure, because the Earth does not orbit the sun in
Middle-earth calendar the three extra days in every third "yén" (once every 432 years), for an average year length of ≈365.24306 days. In Rivendell, the "loa" began on the spring equinox and was divided into six "months" or seasons, as follows. Five other days, two between "coirë" and "tuilë" and three between "yávië" and "quellë", meant the calendar added up to 365 days. Irregularities were allowed for by adding another three days every twelve years, except the last year of a "yén". The calendar developed by the Men of Middle-earth is called the King's Reckoning, and is in many ways similar to