I have a set of data that includes IP in column1 with header IP_Address
there are multiple rows that have the SAME IP, and I would like to increment the RecordID by 1 based on the IP
you can see a sample of the sanitized data below.

I am looking to get a record number added in the last column starting at 1 and as it finds a new IP in increment +1
so it would resemble this

I am trying to use the Multi-Row Formula tool

It almost works but it isn't incrementing correctly.
Would anyone be able to help me out with the correct formula or tool for this?