Perpetual calendar with monthly pages - uses fourteen or twenty-eight pages to cater for leap years and varying length months

摘要

The perpetual calendar uses a set of fourteen pages. Each page is divided up into twelve sections for the months of a year. Those numbered one to fourteen represent the ordinary years, those numbered eight to fourteen represent the 'leap' years. A sheet representing a selected year is chosen according to its number. - An alternative design uses twenty eight pages. Where sheets one to seven represent the 28 day months, sheets eight to fourteen the 29 day, sheets fifteen to twenty-one the 30 day months and sheets twenty-two to twenty-eight the 31 day months. Each group contains 7 pages each starting on a different day of the week.