The Romans did not number days of a month sequentially from the 1st through the last day. Instead, they counted back from the three fixed points of the month: the Nones (5th or 7th, depending on the length of the month), the Ides (13th or 15th), and the Kalends (1st) of the following month. The Nones of February was the 5th, and the Ides the 13th. The last day of February was the "pridie Kalendas Martias," "day before the Kalends of March". Roman counting was inclusive; February 9 was "ante diem V Idūs Februarias," "the 5th day before the Ides (13th) of February," usually abbreviated "a.d. V Id. Feb." (or with the "a.d." omitted altogether); February 23 was "VI Kal. Mart.", "the 6th day before the Kalends of March."