Assuming the membership column # is B, set your conditional format in
cell B-2 to "cell value", "is equal to" =B1 Then use the formula
brush to copy it down to the end of column B. All the duplicated
numbers will "format" the color you pick, except the first one in each
set of duplicated numbers.

If you want ALL the duplicate #s highlighted start with cell B-1 and
put a second condition in cell B-1 "cell value" "is equal to" =B2
and copy it down the entire column. This condition alone will
highlight all but the last duplicated number.

ed


SGT Buckeye wrote:
I have a column that contains 528 membership numbers sorted in
ascending order. Some of the membership numbers are duplicates and
each is 8 or 9 digits long. I would like to apply conditional
formatting to this column to identify the duplicates so I don't have to
go through and do this manually. Please help.