If they're in one column...

Select the range
data|text to columns
choose fixed width and remove any lines that excel guessed
choose Date (ymd)
and plop it in the same range as where you picked it up.

And format those (now real) dates the way you want.

DJ wrote:

I have been given an Excel spreadsheet with numbers in 8-digit text format.
For example, 20020812 would be August 12, 2002. How do I convert these to
some sort of date field that will allow me to perform calculations (count
days from one date to the next)?

--

Dave Peterson