A leap cycle of **293 years** contains exactly 71 leap days, 52 leap weeks or 13 leap months (of 4 weeks each) and thus overall 107016 days, 15288 weeks and 3822 four-week months or 3516 twelfth-of-a-year months. Its mean year length is ca. 365.242321 days or 365 days, 5 hours, 48 minutes and ca. 56.5 seconds. A peculiar detail of the number of leap weeks and leap months is that they add up to another year, i.e. the cycle is equal in length to one of **294 years** of 364 days each.

Probably the most prominent use cases for this leap cycle are the Symmetry454 and Symmetry010 Calendars created by Irv Bromberg, who proposes a leap rule that spreads leap items equally across its length thereby minimizing astronomic “jitter”.

All items (13)

Community content is available under CC-BY-SA unless otherwise noted.