I think part of the answer to your problem lies not with you but with your user. If they are entering transactions one or two weeks late they cannot expect to have a valid weekly valuation. Your system just does not have the information to correctly calculate values because the user has not entered it. They cannot expect your application to be psychic.

If it were me I would use the advice that has been given by earlier posts and produce valuations based on the entered information. I would have a warning to that effect on all displays and reports and I would highlight any items with negative stock because purchases had not been entered but sales had as cases of missing or incorrect data. I would make sure that I had a few utility programs (queries and the like) handy so that when the user objected to the reports I could show that the values that they objected to were a result of the data entered (or not entered) at the time the report was produced. To this end, make sure that all transactions record the date and time of entry as well as the date and time of the transaction.

If all data is entered at the time the transactions occur then a running total will be accurate. Once a backlog is entered then the running total will once more be accurate. The problem occurs in the period before the backlog is entered, and that is the user's operational problem, not a problem with your system.

>Hi,
>Thank you.
>Don't know should I ask this question again, since I ask before. However, I still can't get it.
>
>Since, weighted cost will be calc and stored in stock header file and also with transaction file. What would you do if user do backlog job like key in purchases for last week? Then the weighted cost in stock header and transaction will be incorrect.
>
>BTW, my application allow user to generate stock ledger/stock valuation report from period, eg. only from last monday to last friday.
>
>Thank you