The Ethiopic calendar has twelve months of thirty days plus five or six epagomenal days, which comprise a thirteenth month. The Ethiopian months begin on the same days as those of the Coptic calendar, but their names are in Ge'ez. A sixth epagomenal day is added every four years, without exception, on August 29 of the Julian calendar, six months before the corresponding Julian leap day. Thus the first day of the Ethiopian year, 1 Mäskäräm, for years between 1900 and 2099 (inclusive), is usually September 11 (Gregorian). It falls on September 12 in years before the Gregorian leap year, however.