Issue No Negative with Costing Method Average
Solution

Why you shouldn't ask and allow the client to go in Negative Qty if the costing method is average. Explanation is attached hereby see the calculation as it makes sense for us and NAV but not to the clients.

As NAV average costs application method is FIFO and it is calculated on the basis of Valuation Date. At every exit (i.e. outbound entry) the COGS is Weighted Average of qty received on or before the valuation date of the outbound entry.

          
Valuation Date Item No. Unit Cost Cost is Adjusted Entry Type Quantity Cost Amount (Expected) Cost Amount (Actual) Running Cost Running Quantity Running Average
23/01/2008 43577 11 No Sale -20 0 -220 -220 -20 11
31/01/2008 43577 11 No Sale -50 0 -550 -770 -70 11
18/02/2008 43577 13 No Purchase 100 0 1,300.00 530 30 17.66666667
29/02/2008 43577 12.68 No Sale -25 0 -317.02 212.98 5 42.596
07/03/2008 43577 12.68 No Sale -10 0 -126.81 86.17 -5 -17.234