just include an IF in your formula. For example, if , F4 contains Formula1
change it to =IF(Formula1<0, 0, Formula1)
This will check if the result is less than zero; if so, it will insert a zero, if not, it will calculate the actual result.
If your original formula is quite lengthy, this new formula will, of course, be twice as lengthy. An alternative would be to store the raw result in another location, perhaps a hiden one, then test that result in the desired location (F4 in my example).
Hope this helps
Frank
I am using formulae to generate values in Excel . How can I have the cell show zeros when it's a negative value ?

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