 The first leap day was in 22 BC, and they occurred every four years from the beginning, even though Roman leap days occurred every three years at this time (see Leap year error).This calendar influenced the structure of several other reformed calendars, such as those of the cities of Gaza and Ascalon in Palestine, Salamis in Cyprus, and the province of Arabia.It was adopted by the Coptic church and remains in use both as the liturgical calendar of the Coptic church and as the civil calendar of Ethiopia.