The Accumulative Table of Days shows the number of days from January 1, 1980 to December 1, 2025. Each day is represented by a figure which can be ascertained by adding the day of the month to the number designated for that month; thus, December 31, 1982 is represented by 6,543 + 31, or 6,574.

To determine the date when a given period will expire, add to corresponding number of date selected, the number of days in said period; by subtracting from the number thus obtained, the next lowest number shown on the table, you will have the day of the month to which said period extends (but not inclusive).

Thus:

The inclusive dates of the 215 week period are June 2, 1982 through July 15, 1986.

To determine the number of weeks between two dates, ascertain the respective numbers for said dates and subtract, dividing the difference by 7; for example:

Note: This period includes March 25 but not July 13. If the first day is to be included, add one day.