Open the 
Item Journal
window.
On each journal line, fill in the fields. For Help about a specific field, click the field and press F1.
Click Posting, Post.
It is sometimes necessary to make adjustments to the quantity on inventory, for example, if there is inventory shrinkage or items are not fit for sale.
Open the Item Journal
window.
On each journal line, fill in the fields. For Help about a specific field, click the field and press F1.
Click Posting, Post.
Making Negative Adjustments to Inventory Value