Transfer birthdays from one year to next in excel

Nonemjar 

You should consider an alternative to storing each month on a separate worksheet, particularly if you have nothing to specify for the birthdays/repeating events but a person's name (or other static text). A single calendar – on a single worksheet – can work for all months and years. See the attached workbook.

On the Calendar worksheet, you choose a month (cell B2 is a dropdown list) and enter a year (in cell C2). Formulas in the odd-numbered rows (below the weekday names) derive which day numbers to display; different formulas in the even-numbered rows use a FILTER function to pull events/birthdays from the table on the Events worksheet that should be displayed for the selected month.

The Events worksheet contains the list of events and birthdays in an Excel table. For most entries, the Month-Day column contains the month number and the day of month. The formulas in the Date column generate date values for a specific year (from cell D1, which is a copy of the value that was entered on the Calendar worksheet).

(If you are wondering: Yes, multiple table rows can refer to the same generated date. All entries for one generated date will be concatenated into one Calendar cell, separated by the character(s) in cell D1 on the Calendar worksheet.)

Somewhat more complicated formulas can calculate repeating events that do not occur on the same day each year, e.g., World Honey Bee Day (the third Saturday in August). These can be readily copied to another table row and adjusted for use in a different month.

Note that while the Description column almost always contains only text, cells here can contain formulas, such as calculating a person's age on their calculated birthday. See Jane Goodall in April as an example.