WIP for specific period does include all costs

I need to run a WIP report for a specified period that includes committed costs, that have not been received.  Our current practice is to receive the goods when the invoice is received, in order to insure the dollar amount is correct, and to use the invoice number issued by the vendor.  We currently use a report called PO Expected deliveries by Job, to calculate our month end accrual, and update our cost for WIP reporting purposes to our bonding company.  How anyone found a report in the system or a work around for this problem.