Pivot Calculate Grand Total Average

[goss]

Hi all,

Using Excel 2010.

My Pivot is including 0 values in calucation for Grand Total Average so that 100,0,100,0 = 50
Can I exclude the zeroes from the Grand Total Average

Barring that, how can I add a calculated average to replace the Grand Total Average

I tried adding a calculated field =IF(Field<>0,1,0), but I could not add to the right of the Pivot only to the Values Field.
I guess that might be ok, might be needed for calculation, but I can I make it invisible/hidden field? I do not see an option on the toolbar.

thx
w