There are several factors taken into consideration when the minimum stock (MINSTOCK) shortage and the date for purchase of this quantity is defined in the Purchase application (PUR).
The system goes through each product to find the necessary information and adds this to a table on the part. The job identifies stock quantity, customer links, production links, dates, locations and more. The lead-time on the part will affect the calculation too.
When done, the customer quantity is deducted from supplier quantity and the shortage is defined.
The shortage will appear in the week when the supplier quantity (SUPQTY) minus the customer quantity (CUSQTY) is less than the minimum stock (Minstock) value for the first time.