Calculating Age Using Dates

[Branu Ags]

In Stata, I need to calculate the age of a patient at the last check-up by using the date of birth and the check-up date. All the data is inputted via spreadsheet. The dates in the spreadsheet are formatted like this: 6/12/57, 8/1/08, etc. I am unsure on how to convert the string to an integer for subtraction and not sure on how to correctly write the dates (or how to change all the dates to fit the format). I have a large data set so it would seem impractical to individually change each date.

[William Lisowski]

This would be easier to address if you were to first import the spreadsheet into Stata (using import excel) and then use the dataex command to provide a example of your data as it is imported into Stata.