Bài giảng môn học Quản trị kinh doanh - Chapter 7: Managing inventories

Copyright © 2014 McGraw-Hill Higher Education. All rights reserved.CHAPTER 7Managing InventoriesMcGraw-Hill/IrwinLearning ObjectivesLO7-1 Define the different types and roles of inventoryLO7-2 Explain the financial impact of inventoryLO7-3 Explain and compute measures of performanceLO7-4 Calculate inventory policy parameters to minimize total acquisition cost LO7-5 Determine the cost of a company’s service level policyLO7-6 Explain the advantages and disadvantages of different inventory location strategiesLO7-7 Describe practical techniques for inventory planning and management7–2Inventory: supply of items held to meet demandCustomersSuppliersRaw MaterialComponentsMROMaintenance, repair & operating suppliesDistributionWork in Process (WIP)Finished Goods (FGI)CustomersSuppliersRaw MaterialComponentsMROMaintenance, repair & operating suppliesDistributionWork in Process (WIP)Finished Goods (FGI)Transportation7–3Types of InventoryLO7-1Financial Impact of InventoryLO7-27–4Measures of Inventory Performance:Inventory TurnoverInventory turnover: ratio of average inventory on-hand and level of sales = Cost of goods sold / Average inventory at cost= Net sales / Average inventory at selling price= Unit sales / Average inventory in unitsWith an annual cost of goods sold of $500M and average inventory of $80M.Inventory turns = $500/$80 = 6.25 turns7–5Example 7-2LO7-3Measures of Inventory Performance:Days, Service Level, Stock outsDays of Supply: length of time operations can be supported with inventory on-handDays of supply = Inventory/Daily demandIf inventory is 2M and daily demand is 25,000 dayDays of supply = 2M/25,000 = 80 daysService Level: ability to meet customer demand without a stock outStock out: no inventory is available7–6Example 7-3LO7-3Independent Demand: demand is beyond control of the organizationDependent Demand: demand is driven by demand of another item7–7Inventory Management SystemsLO7-4Continuous Review Model Continuous Review: inventory levels are constantly monitored to determine when to place a replenishment orderUnits in InventoryTimeAverage InventoryOrder PointFigure 7-17–8LO7-4Total Acquisition Costs Total Acquisition Costs: sum of all relevant annual inventory costsHolding costs: associated with storing and assuming risk of having inventoryOrdering costs: associated with placing orders and receiving supplyTAC = annual ordering cost + annual carrying cost7–9LO7-4Economic Order Quantity (EOQ) Economic Order Quantity (EOQ): minimizes total acquisition costs; point at which holding and orders costs are equalHow much to orderD = Annual DemandCo= Ordering costU = Unit costCi = Holding cost7–10LO7-4Periodic Review ModelOrder Interval: fixed time between inventory review, on-hand level is unknown during this uncertainty periodUP = Uncertainty periodOI = Order interval t = average lead time d = average lead time z = standard deviations needed for service level = standard deviation of demand during the uncertainty period A = inventory on hand7–11LO7-4Single Period Inventory Model Single Period Inventory Model: items are ordered once, and have little left over value (newsvendor problem)Target Service Level: probability of meeting demand7–12LO7-4Managing InventoryManaging Cycle Stock: reducing lot sizesManaging Safety Stock: using ABC analysis and reducing lead timeManaging Locations: balance inventory, lead time and service levelsImplementing Inventory Models: matching management system to specific items7–13LO7-6Inventory Information Systems and Accuracy7–14LO7-7Managing Inventories SummaryThere are multiple types of inventoryInventory fulfills multiple rolesInventory is an asset, and has multiple costsAn inventory policy determines how much and when to orderContinuous systems monitor on-hand levels Safety stock levels are linked with service levelsPeriodic systems count inventory at specific intervalsNumber of storage locations impact inventory levelsManagers should work to reduce inventory levels7–15