Subtracting and adding from a stock sheet according to the item code

This one may be impossible, a challenge or ridiculously easy but I cant get my head around it.

In the attached stock take sheet, I have a job requisition form, on that form I have 3 columns ("B","C","D")
The columns are labelled as follows
O - amount of items ordered
R - amount of items recieved
Rt - amount of items returned

I have a simple lookup formula for item code which then brings in the item description, stock quantity, cost, etc into the job requisition.

Ok now that you have a background on whats going on, Heres what I'm hoping to accomplish,

I want excel to subtract items from stock if an amount is entered into the items recieved column
and to add the items to stock if an amount is entered into the items returned column,

Obviously the problem comes in that it most use the item code as a reference to know which stock item to subtract or add to.

Is this possible?

Attached Files

• COPY of Stock control test ver 1-0.xlsm‎ (51.2 KB)