Work with dates
Build a date from a year, month and day
=DATE(A2,B2,C2)How it works in Excel
- A2 is the year.
- B2 is the month.
- C2 is the day.
- Numbers past the end of a month roll forward, so month 13 is January of the next year.
- Format the cell as a date if you see a plain number.
The idea in general
It joins three separate numbers into one real date that Excel can do math with.
What I assumed
- The year, month and day are in A2, B2 and C2.
Check the result on your own data before relying on it.