См.: количество заказа.
order quantityorder quantity - - The selling point should order the difference between its current on-hand inventory and the buffer target level adjusted for any adjustments in the buffer level minus in-transit inventory (inventory already ordered but not received).
Example: Suppose the buffer target is 300 units, current on-hand inventory (buffer status) is 225 and 20 units are in-transit. Order quantity is therefore:
Order quantity = buffer target - (current on-hand inventory + in-transit inventory) = 300 - (225 + 20) = 55 units