How about:

b1: 1 [format as "000"]
b2: =if(a2<a1,b1+1,b1)
Copy down

Regards,
Fred.

"Vijay DSK" <Vijay wrote in message
...
Hi all,
Thanks for this forum for the help rendered in my previous issues.
Now stucked up with another one.
It is like ....
col1 col2
1
2
3
1
2
3
what i am looking is in column 2 a formula or function which gives as
follows
col1 col2
1 001
2 001
3 001
1 002
2 002
1 003
Hope i am clear in asking the question