I would like to calculate a cumulative of:

A1 = 3.2
B1 = 9.5
C1 = 6.9

I want D1 to be the result of the cumulative of A1, B1 and C1 only if they
have a value different than 0. I want to be able to have a cumulative even
though one of them has 0 as value.

Any Help