Leap year most years that are multiples of 4 are leap years. In each leap year, the month of February has 29 days instead of 28. Adding one extra day in the calendar every four years compensates for the fact that a period of 365 days is shorter than a tropical year by almost 6 hours. Some exceptions to this basic rule are required since the duration of a tropical year is slightly less than 365.25 days. The Gregorian reform modified the Julian calendar's scheme of leap years as follows: Over a period of four centuries, the accumulated error of adding a
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