Cummlative on packing list

Where do you enter your cummlative for a release for it to calculate with each shipment

I would like to know too, especially as it relates to a back order or when you reprint a packslip.

I have not used Epicor EDI, but I believe this may be related to demand management. In another life CUMS (Cumulative quantity shipped) were a field on the EDI 862. I could be wrong on this, but the field sounds like the same thing as what I am describing.