Leap week calendar week calendars would synchronize with the Gregorian every 400 years Note that the new years of the calendars shown need not be synchronised. The years according to ISO week date applied to months, i.e. a month has as many weeks as it has Thursdays, are shown depending on the weekday of 1 January, shaded weeks belong to the month they are labeled with in regular years and to the other adjoining one in leap years. Leap week calendar A leap week calendar is a calendar system with a whole number of weeks every year, and with every year starting on
Positivist calendar Positivist calendar The positivist calendar was a calendar reform proposal by Auguste Comte in 1849. Revising the earlier work of Marco Mastrofini, or an even earlier proposal by "Hirossa Ap-Iccim" (Hugh Jones), Comte developed a solar calendar with 13 months of 28 days, and an additional festival day commemorating the dead, totalling 365 days. This extra day added to the last month was outside the days of the week cycle, and so the first of a month was always a Monday. On leap years, an additional festival day (also outside the week cycle), to celebrate holy women, would join the