Thanks Herbert... Can you explain why the =Sum(1/Countif(range, range)) -
range2 worked the way it did for you... I didn't seem to be able to replicate
it. (by the way, it was enclosed in { }, I don't know if that was
intentional or a product of the download.

By the way... I believe I got another solution to my problem too - at least
in Excel 2007 - you can "group" the 51st to end customers and hide the
detail, showing only the total for the group.
--
Jeff


"Herbert Seidenberg" wrote:

Use Pivot Table function "Top 10" instead of "Group"
This will download to Excel 2007 also:
http://www.freefilehosting.net/download/3acdf