Hi,
try

=SUM(Sheet2:Sheet12!A1)/COUNTIF(Sheet2:Sheet12!A1,"0")

This will divided by the number of cells with values greater than 0, so if
you have a cell with no information it will not consider it

"S. Kissing" wrote:

I have 13 sheets, Jan - Dec and a total sheet. I want to average cells in
the Jan - Dec sheets. If I add my formula to the sheets then my average
counts each sheet (12) I know I can add if statements to divide by only the
shhets with valuses 0 in the cells however it is becoming very very
long...is there a short cut I am missing? Thanks