subtract 2 cells and get blank instead of 0.0

[tpeter]

I have templates set up to subtract cell A1-B1 and a colume that shows me the
amount of change. The default cell value even if A1 and B1 are blank is 0.0.
On a different sheet I have the compiled data that shows me the average and
std dev of all the runs. For the grand total I am using the function:

=AVERAGE(IF(ISNUMBER(H3:H202),H3:H202)) (used the CSE)

This works fine but this is a template and the reason for this function is
to not have to delete unused rows. When I have unused rows it is still using
the 0.0 because it is number. How do I change the subtraction so it doesn't
give me 0.0 until data is entered into cell A1 and B1? Example is =a1-b1
returnes 0.0, I want it to be blank.

Thank you for your help.

Tim

 

[Gary''s Student]

=IF(A1-B1=0,"",A1-B1)
but be careful of rounding.

 

[tpeter]

I figured it out, just changed core values to an if statement
=if(a1="","",a1-b1)

 

[klswvu]

If your values are positive only...
=AVERAGE(IF((H3:H203>0),H3:H203)) (Use CSE)