Queries/Workbook USAGE

Hi,

My task is to find out least used queries & workbooks so we can clean up unused queries & workbook. I ran BW STATS queries on 0BWTC_C10 and able to see some information on queries but I can't find any information for Workbooks like usage, Last Used date etc. from BC queries that are build on BW statistics Info Cubes & Multi provider.

Where we can find these type of information??

I would appreciate if some one can helo on this issue as it is very urget and need to give status by end of today.

Thanks

BI Cosultant