Data entry expression

[umusbkraz]

I have a data entry form linked to a table. The table is a log of work orders on the production floor which have been audited by Quality Assurance. I am moving from a paper form with manual entry to direct entry by the QA auditors. To speed data entry we are using a bar code scanner to input most of the data. The bar code/data on the work order cover sheet has the work order quantity + one because they print an extra label as a retention sample. How can I scan the barcode and have the value minus one go into the table, and if possible show on the form as well. For example the work order quantity is 64, but the bar code has a value of 65. There is quite a bit of data in the table already so I do not want anything I do to change what is already there.

[June7]

Ideally, would not save aggregate data. Save transaction records then calculate the net balance when needed. Review http://allenbrowne.com/AppInventory.html

[umusbkraz]

Sorry, I guess I made the question much more complicated than I wanted. I have a form with a work order quantity field. The bar code scanner reads a number 'X' into the field in the form. I want X-1 to go into the corresponding field in the table.

[Homegrownandy]

Have the scanner information save "as is" then manipulate it with a calculated field. eg.

work_order_quantity: scanned_quantity -1

just out of curiosity, wont the 1 be 2 after the first run? every time there is an extra label this would increase?