I have created a formula (excel 2003) to output a "1" if duplicates are found in a column.

=IF(COUNTIF(A$2:A$10750,A2)>1,"1","")

For some reason this formula does not mark the last duplicate in the in the file for all groups of duplicates. So if "Steve" is mentioned 4 times in column A, it will only mark the top three entries. If "Mike" is mentioned 6 times, it will only mark the first 5.

Any help is greatly appreciated!

`+1`

into the formula), but Excel is doing exactly what you told it to do. – user3463 May 18 '12 at 5:49