Proleptic Julian calendar with year 0 corresponding to 1 BC, and "year −1" corresponding to 2 BC, so that in this system, Julian leap years have a number divisible by four. The determination of leap years in the proleptic Julian calendar (in either numbering) is distinct from the question of which years were historically considered leap years during the Roman era, due to the leap year error: Between 45 BC and AD 4, the leap day was somewhat unsystematic. Thus there is no simple way to find an equivalent in the proleptic Julian calendar of a date quoted using the Roman pre-Julian calendar
Aztec New Year 22nd. This 365-day calendar was corresponded with the solar year, was divided into 18 'months' of 20 days each, plus 5 'nameless' days at the end of the year. Also, there are some codices that show the existence of the leap year. Aztec New Year The Aztec New Year ( or "Año Nuevo Azteca"; , ) is the celebration of the new year according to the Aztec calendar. The date on which the holiday falls in the Gregorian calendar depends on the version of the calendar used, but it is generally considered to occur at sunrise on March 12. The