What is the best way to monitor monthly change rate for RP CGs

Hi,

I am relatively new with Recover Point. I have four CGs replicating and pretty much set the journal space based on the 20% of the GC group recommendation. I downloaded the Journal Calculator Excel file and there are fields to input for monthly change rate. Is the only way to get this data is for me to ask the application teams? I was wondering if there was a report I could run, etc, M&R, or something to get this info.

Thanks in advance,

Admingirl