In your sum formula...i.e. =A5 + B5 + C5... you can insert an if statement
for the case where the value may not be a number for example PTO is written
in C5

=A5 + B5 +if(isnumber(C5),C5,0)

Hopefully this helps.

"John Krsulic" wrote:

I am trying to create what I would call an if/then formula in Excel 2003. If
someone types the letters PTO into a cell have tat equal zero in the formula.
I have a sum formula of a set of cells I want Excel to be able to add a zero
into the formula if someone types the letters PTO into the cell. My formula
works great until someone types letters into a cell then - of course -I get a
value error in the cell.