We use a lot of BOMs in our manufacturing process. 

These show up on our stock valuation report as negative values until they are booked out in the works order, at which point they are removed from the report and the stock value increases. 

We don't understand enough about the report to work out how these negative figures are effecting the stock value. 

The BOMs are set as FIFO. 

The BOMs all have quantity (Including Unconfirmed) - 0 

Quantity - Negative Number 

Value (Including Unconfirmed) - 0 

Value - Negative Value.

Each BOM is usually made for a specific order, they are bespoke so we don't tend to hold excess quantities in stock. 

We create the works order with a BOM, allocated and issue the stock. Once the product is made they are booked out and the works order is completed. 

Does the BOM negative value cancel out the individual stock item value? 

Why would the stock valuation increase once the BOM is completed if the BOM has used the stock?