I want to SUM two cells in an Excel worksheet but only if there is a value in
both cells. For each month of the year I want to show total minutes (B32:43)
less minutes used (D32:43). The answer will be in (E32:43). However if I use
the simple SUM function =SUM(B32-D32) I get the total minutes in Column E if
there is nothing in column D. I've looked at SUMIF but cannot figure out how
to use it for this purpose. Thanks for your help.