All dates are given as Gregorian or proleptic Gregorian calendar dates. Many mayanists convert Maya calendar dates into the proleptic Gregorian calendar. This Kaliyuga began in the year 3102 BCE in the proleptic Julian calendar. Thus, the year 1 BC of the proleptic Julian calendar is a leap year. A proleptic calendar is a calendar that is applied to dates before its introduction. The year 1400 was not a leap year in the Proleptic Gregorian Calendar. Proleptic Gregorian dates vary substantially from astronomical dates. It is also a leap year starting on Saturday, in the Proleptic Gregorian calendar. Proleptic symptoms result from the development of tissues earlier than usual.