Unless you want to hardcode each cell, you should trap the errors
instead of leaving them as "expected errors". This is good practice
anyway.

For example, instead of

P10: =N10/O10

where O10 may be zero, use

P10: =if(O10<0,N10/O10,"")


SUM() (and SUMPRODUCT()) will then ignore the null string.


In article ,
Sam wrote:

This is where I'm having trouble. Thanks for all your help!