Field help (WALLTXT) 

The display of information related to stock availability depends on the setup of the Order entry transaction.
As for the document valuation, the display of the product availability is conditioned by the value of parameter SOHVALLIG - Order valuation on line (VEN chapter, MIS group).

When the total quantity to be allocated is not available, the quantity remaining to be allocated is mentioned. It is expressed in stock unit and sales unit.