Hi,
the BI statistics provide a very good way to analyze the size of a lot of BI objects (Cube, DSO, Info Object, etc.). Multiprovider 0TCT_MC25 contains the relevant data for the "Database Volume Statistics". Main key figures are the size (e.g. in MB) and number of data records.
-> help.sap.com
Here's a screenshot from a report like we use it:
Kind regards,
Oliver.