Summarize Archived Data

Hi,

I'm trying to make a case for storage expiry. One particular thing I'm after is a way to summarise the archived data by date, sent/received date, something like a count for specific periods (months/years). Size info would be nice but not a show stopper. It's hopefully a onetime thing.

Something like this would be perfect:

Period                      Archived Items                         Size GB
June 2010                2,000,000                                 150 GB
July 2010                 1,800,000                                 130 GB
August 2010             1,700,000                                 124 GB

Any Reports/Tools I can use?

Any SQL queries I can run? There is an 'IDDateTime' in the saveset table, can I use this to count archived items? or which table/columns could I query?

Any help greatly appreciated,

Thanks