Hi all,

I'm VERY new to Excel and I'm trying to understand how to tell it to activate a formula I have already inputted ONLY when there is a value greater than zero. It's a very simple formula [=SUM(N15:R15)] but due to the nature of a further formula it is vital to, I need it to only activate when there is actually a value put into the row as when it is blank, it is giving a value of 0 meaning that the other formula is giving an incorrect answer.

In case you're wondering, the other formula is supposed to give an ongoing, increasing figure based on the difference between a previous value and the current one over time. A little hard to explain but this is the formula I've created, maybe there's a simpler way to do it?

=SUM(SUM(N4:R4)+(SUM(SUM(N5:R5)-SUM(N4:R4)))+(SUM(SUM(N6:R6)-SUM(N5:R5)))+(SUM(SUM(N7:R7)-SUM(N6:R6)))+(SUM(SUM(N8:R8)-SUM(N7:R7)))+(SUM(SUM(N9:R9)-SUM(N8:R8))))+(SUM(SUM(N10:R10)-SUM(N9:R9)))+(SUM(SUM(N11:R11)-SUM(N10:R10)))+(SUM(SUM(N12:R12)-SUM(N11:R11)))+(SUM(SUM(N13:R13)-SUM(N12:R12)))+(SUM(SUM(N14:R14)-SUM(N13:R13)))+(SUM(SUM(N15:R15)-SUM(N14:R14)))+(SUM(SUM(N16:R16)-SUM(N15:R15)))+(SUM(SUM(N17:R17)-SUM(N16:R16)))+(SUM(SUM(N18:R18)-SUM(N17:R17)))+(SUM(SUM(N19:R19)-SUM(N18:R18)))

If that makes any sense to you, you might understand that any zeros further down will have an adverse affect on that sums outcome so I'm trying to stop the formulas from activating until a value is put in instead of if being blank and defaulting to zero.

I hope this gives a good enough explanation for somebody to be able to help me but I know my information is far from ideal!

Thanks