Inventory count date change.

Hi,

I had created a PI count doucment using transaction MI09 ( count without reference to a document ) with today's date.

But duing Posting the difference i felt that, the date should not be todays date but it should be last date of the previous month.

How to handle this scenario, I had tried to change the date in teh MI09 document, but in vain.

I need your expertise to proceed further.

Regards,

RitiG