Hello,
another option is to run a Data Volume Management Self-Service on your Solution Manager system. During this self-service the managed system (i.e. the system in question) is analyzed and the saving / archiving potential per archiving object / table determined.
For further information you may look into the presentation 'DVM WoC (Masterslide deck) which can be found on
http://wiki.scn.sap.com/wiki/display/TechOps/Data+Volume+Management in the section 'Useful Links' on the lower left of the page.
The information on the Self-Service starts at page 44.
Best regards,
Claudia