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A leap cycle of 62 years contains 15 leap days and thus overall 22645 days or 744 twelfth-of-a-year months or 3235 whole weeks. Its mean year length is 365.2419355 days or 365 days, 5 hours, 48 minutes and 23 seconds. This leap cycle somewhat overcompensates the bias of the Julian 4-year and the Gregorian 400-year leap cycle.

One interesting property is that six cycles have 4601 lunations spanning 372 solar years. The resulting mean lunation length is 29.5305368 days or 29 days, 12 hours, 43 minutes and 58 seconds. For even more precision one could insert one more leap day after sixty 62-year cycles, or ten 372-year lunar cycles. That results in a mean year length of 365.2422043 days or 365 days, 5 hours, 48 minutes and 46 seconds and a mean lunation length of 29.5305586 days or 29 days, 12 hours, 44 minutes and 0 seconds.

Leap rule[]

The Julian 4-year leap cycle sets 15 leap days in 60 years. There are two additional years in this cycle, which means two subcycles of 5 years or one subcycle of 6 years. The benefit of the latter is that leap years are always even numbers (or odd, if you fancy it).

It is also possible to combine two cycles into a 124-year cycle with one skipped olympiad.