Zil, if your sheets are named firstsheet and lastsheet try this to sum A1

=SUM(firstsheet:lastsheet!A1)



--
Paul B
Always backup your data before trying something new
Please post any response to the newsgroups so others can benefit from it
Feedback on answers is always appreciated!
Using Excel 2002 & 2003


"zil" wrote in message
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My formula SUM(firstsheet:lastsheet) returns a #VALUE! error Why?