A perennial calendar is a calendar that applies to any year, keeping the same dates, weekdays and other features. Perennial calendar systems differ from...

in 1902. The International Fixed Calendar divides the year into 13 months of 28 days each. A type of perennial calendar, every date is fixed to the same...

allowing benefits of a perennial calendar to be shared by all. Some calendar reform ideas, such as the Pax Calendar, Symmetry454 calendar and the Hanke–Henry...

of Brooklyn, New York in 1930. The World Calendar is a 12-month, perennial calendar with equal quarters. Each quarter begins on a Sunday and ends on a...

calendar more accurate, the Hanke–Henry Permanent Calendar focuses on making the calendar perennial, so that every date falls on the same day of the week...

proposed reforms to the civil calendar, in order to achieve a perennial calendar. Some, however, such as the ISO week date calendar, are simply conveniences...

The Pax calendar was invented by James A. Colligan, SJ in 1930, as a perennializing reform of the annualized Gregorian calendar. The common year is divided...

for the next year. With perennial calendars, the same representation of the year serves for every year. Perpetual calendars, in this context, are computation...

the International Fixed Calendar and the Pax Calendar. Technically, these are not perpetual calendars but perennial calendars. Their purpose, in part...

and July 1 on leap years. This model would be a perennial calendar, with each date occurring perennially on the same day of the week. Grosclaude lists many...