You don't need SUMPRODUCT

If these values start in row 2 and go down to row 25, then in col C use

=B2/COUNTIF($A$2:$A$25,a2)

"SteveC" wrote:

What formula should I use in Column C to return the % figures in Column C?

This formula in Column C should rank in percent the numerical rank in Column
B for Each Label indicated in Column A.

For example, in the first row below, it shows that 4 in Col B is in the top
57% of the 7 Xs in Col A. The manual formula is =4/7.

Could you also explain generally what the sumproduct formula that should be
used with this is doing in English? Thanks a lot!

Col A Col B Col B
X 4 57%
X 7 100%
X 2 29%
X 1 14%
X 5 71%
X 6 86%
X 3 43%
XX 4 100%
XX 2 50%
XX 1 25%
XX 3 75%
XXX 1 14%
XXX 3 43%
XXX 6 86%
XXX 4 57%
XXX 7 100%
XXX 2 29%
XXX 5 71%
XXXX 2 50%
XXXX 3 75%
XXXX 4 100%
XXXX 1 25%