=SUMIF(A:A,5,B:B)/SUM(B:B)

Regards

Trevor


"Godot" wrote in message
...
I have the following columns of data:
Column A Column B
Product Number of faults
1 5
5 1
6 2
5 3
What formula (or set of formulas) will be able to tell me the proportion
of
Product number 5's that have more than one fault? (Note - I want a formula
that does not require an autofilter to be applied to my columns of data)

Thanks