Have you tried

=AVERAGE(sheet1:sheet13!B2)

Average will ignore the cells that have no value in them

In your first formula you were omitting the cell reference for each
sheet.

HTH

Ed


--
EdMac
------------------------------------------------------------------------
EdMac's Profile: http://www.excelforum.com/member.php...o&userid=30736
View this thread: http://www.excelforum.com/showthread...hreadid=540150