The Bahá'í calendar, also called the Badí‘ calendar, used by the Bahá'í Faith, is a solar calendar with regular years of 365 days, and leap years of 366 days. Years are composed of 19 months of 19 days each, (361 days) plus an extra period of "Intercalary Days" (4 in regular and 5 in leap years). Years in the calendar begin at the vernal equinox, and are counted with the date notation of BE (Bahá'í Era), with March 21, 1844 CE being the first day of the first year. The period from March 21, 2007 to March 20, 2008 is the year 164 BE.