Adding Counter to column for number of identical file numbers

[Sam]

Is there a formula or easy way to add a counter to a file? For example
if I have a file number that appears on a file 2 times and another 3
times and another 5 times I get the following results.

Column (A) Column (B)
File Number Results
9565845 1
9565845 2

9552456 1
9552456 2
9552456 3

5695695 1
5695695 2
5695695 3
5695695 4
5695695 5

 

[Bernie Deitrick]

In cell B2, enter this

=COUNTIF($A$2:A2,A2)

or, if you can have blanks and don't want those counted

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

Then copy down column B to match col A.

HTH,
Bernie
MS Excel MVP