Inventory and delivery maths: EOQ, reorder points, safety stock, turnover and Little's Law
Order size that minimises the combined cost of ordering and holding stock.
Stock level that triggers a new order, covering demand during the lead time.
Buffer inventory that absorbs demand variability during lead time.
How many times inventory is sold and replaced in a period.
Average number of days stock sits before being sold.
Average items in a system equals arrival rate times average time in the system.
Average working inventory between deliveries, half the order quantity.
Share of customer demand met immediately from stock.
How fully productive capacity is being used.
How full a vehicle runs — empty space is wasted fuel and money.
Total shipment cost spread across the units delivered.
Fuel spend for each kilometre from fuel price and economy.
Percentage of orders delivered by the promised date.
Product of on-time, complete, damage-free and correctly documented rates.
Rate at which a facility produces or moves goods.
How long a shipment or container sits idle at a facility.
Elapsed time from a customer placing an order to receiving it.