Counting Column and inserting number

[gaby58]

Hello,

I have a particular column which has values like
123
123
124
125
125
125
125 etc, what I want to do is I want to count these and in the next column I want to put it like these, how do I do this?

123 1
123 2
124 1
125 1
125 2
125 3
125 4

Thanks for any tips

[richardreye]

This formula should do the trick. Assuming your values start in cell A1, place 1 in cell B1 (it wil always be 1) and put this in cell B2 and copy it down.

=IF(A2=A1,1+B1,1)

Cheers!