Just-in-Time Purchasing
Juat-in-time (JIT) purchasing is the purchase of materials (or goods) so that they are delivered just as needed for production (or goods). Consider Hewlett-Packard's (HP's) JIT purchasing: HP has long-term agreements with suppliers of the major components of its printers. Each supplier is required to make frequent deliveries of small orders directly to the production floor,based on the production schedules HP provides them.The suppliers work hard to keek their commitments because any failure on their part will result in HP's aSembly plant not meeting its scheduled deliveries of printers.
JIT Purchasing and EOQ Model Parameters
Suppose Glare Shade's managers believe that the current purchasing policies might result result in the carrying costs of the firm's inventories (parameter C in the EOQ model) being much greater e what they had estimated because of higher warehousing, handling, insurance, and equipment costs. Suppose they also believe that the costs of placing a purchase ordee ( parameter P in the EOQ model) is likely to decrease because of the following:
-Glare Shade is estsblihing long-term purchasing agreements that define the price and quality terms it has with its suoliers over an extended period. No additional nego-tiations need to take place before supplies can be ordered.
-New electronic systems allow Glare Shade to place purchase orders,tally delivery records, and make payments to suppliers more cost effectively.
-Glare Shade is using purchase-order cards (similar to consumer credit cards such as VISA and MasterCard). As long as purchasing personnel stay within preset total and individual-transaction dollar limits, traditional labor-intensive procurement-approval procedures are not required..
Exhibit 20-4 tabulates the sensitivity of the EOQ (page 790) to changes in carrying and ordering costs of UX1s. Exhibit 20-4 supports moving toward JIT purchasing because, as the company's relevant carrying costs increase and relevant ordering costs per purchase order decrease, the EOQ decreases and ordering frequency increases.
Relevant costs of JIT Purchasing
JIT purchasing is not guided solely by the EOQ model because that model only emphasizes the tradeoff between relevant carrying and ordering costs. Inventory management,however,also includes accounting for a company's purchasing costs, stockout costs, costs of quality, and shrinkage costs. Glare Shade's managers are concerned that ordering and storing large quantities of UX1 units have contributed to defective and broken units and shtinkage.So,the company begins implementing JIT purchasing by asking the
Economic order Quantity in Units at Different Ordering and Carrying costs
Annual Demand (D) 1,300 units
Relevant Carrying Costs Per unit per Year (C)
Relevant Ordering costs per Purchase Order (P)
sipplier of UX1 units to make more ferquent deliveries of smaller sizes. Glare Shade has recently established an Internet business-to-business purchase-order link with its supplier, Rytek. Glare shade triggers a purchase order for UX1s by a single computer entry. Payments are made electronically for batches of deliveries,rather than for esch in dividual delivery. These changes reduce the company's ordering costs from $200 to only $2 per purchase order! Glare shade will use the Internet purchase-order link whether or not it shifts to JIT purchasing. We next evaluate the effect JIT purchasing has on quality and costs.
Description of ltem
Deliveries Purchasing costs
Inspection of units
Required rate of return on investment
Relevant carrying costs of insurance, materials handling, storage,etc. Customer return costs
Stockout costs
Current Purchasing Practice
1,000 units purchased 13 times per year
$14 per init
Units inspected at the time of receipt at a costs of $0.05 per unit to in identify units that need to be returned
$3.10 per unit of average inventory per year
$10 for shipping and processing a defective unit returned by a customer.The high quality of units supplied by Rytek and Glare Shade's inspection procedures will result in no units being returned by customers.
No stockout costs because demand and purchase-order lead times during each 4-week period (52 weeks /13 deliveries) are known with certainty .
JIT Purchasing Practice
100 units purchased 130 times per year (5 times every2 weeks)
$14.02 per unit (Note:Many companies do not pay a higher price for more frequent deliveries.)
Units not inspented because Rytek ensures that quality UX1 sunglasses are delivered to support Glare Shade's JIT purchasing
$3.00 per unit of average inventory per year (lower insurance,materials handling,and storage rates)
$10 for shipping and processing a defective unit returned by a customer.The high quality of units supplied by Rytek will result in no units being returned by customers.
More stockouts because demand variation and delays in supplyiny units are more likely in the short time intervals between orders under JIT purchasing.Glare Shade eXpects to incur stockout costs on 150 units of UX1 per year under the JIT purchasing policy. When a stockout occurs,Glare shade must rush-order units at an additional costs of $4 per unit.
Should Glare Shade implement the JIT purchasing option of 130 deliveries of UX1 per year? Exhibit 20-5 compares Glare Shade's relevant total costs under the current purchasing policy and the JIT policy. It shows net cost savings of $1,901 per year by shifting to a JIT purchasing policy.The benefits of JIT purchasing arise from lower carrying and inspection costs as a result of better quality. JIT purchasing gives Glare Shade's managers immediate feedback about quality problems by reducing the "safety net" large quantities of inventory afford.
Supplier Evaluation and Relevant costs of Quality and Timely Deliveries
Companies that implement JIT purchasing choose their supporters carefully and develop long-term supplier relationships. Some suppliers are better positioned than others to support JIT purchasing. For example,the corporate strategy of Frito-Lay,a supplier of potato chips and other snack foods, emphasizes service, consistency, freshness, and the quality of the products the company deliver. As a result, Frito-Lay makes deliveries to retail outlets more frequently than many of its competitors
What are the relevant total costs when choosing suppliers? Consider again the UX1 units purchased by Glare Shade. Denton Corporation, another supplier of UX1 sunglasses, offers to supply all the units that Glare Shade needs. Glare Shade requires the supplier to deliver 100 units 130 times per year (5 times every 2 weeks). Glare Shade will establish an Internet-based purchase -order link with whichever supplier it chooses, trigger a purchase order for UX1 units by a single computer entry, and make payments electronically for batches of deliveries, rather then for each individual delivery. As discussed earlier, the company 's ordering costs will be only $2 per purchase order.The following table provides information about Denton versus Rytek. Rytek charges a higher price than Denton but also supplies higher-quality UX1s. The information about Rytek is the same as that presented earlier under JIT purchasing in Exhibit 20-5
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Exhibit 20-6 shows the relevant total costs of purchasing from Rytek and Denton. Even though Denton is offering a lower price per unit, there is a net cost savings of$1,873 per year by purchasing UX1s from Rytek because of lower inspection, customer returns, and stockout costs. The benefit of purchasing from Rytek could be even greater if purchasing high-quality UX1s from Rytek enhances Glare Shade reputation and increases customer goodwill, which could lead to higher sales and profitability in the future.
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JIT Purchasing, Planning and Control, and Supply-Chain
Analysis
Retailers’ inventories levels depend on by the demand patterns of their customers and supply relationships with their distributors and manufacturers, the suppliers to their manufacturers, and so on. The supply chain describes the flow of goods,services, and information from the initial sources of materials and services to the delivery of products to consumers,regardless of whether those activities occur in the same company or in other companies. Retailers can purchase inventories on a JIT basis only if activities throughout the supply chain are properly planned, coordinated, and controlled.
Procter and Gamble’s (P&G’s) experience with its Pampers product illustrates the gains from supply-chain coordination. Retailers selling Pampers encountered variability in weekly demand because families purchased disposable diapers randomly. Anticipating even more demand variability and lacking information about available inventory with P&G, retailers’ orders to P&G became more variable that, in turn, increased variability of orders at P&G’s suppliers, resulting in high levels of inventory at all stages in the supply chain.
How did P&G respond to these problems? By sharing information and planning and coordinating activities throughout the supply chain among retailers, P&G, and P&G’s suppliers. Sharing sales information reduced the level of uncertainty that P&G and its suppliers had about retail demand for Pampers and led to (1) fewer stockouts at the retail level, (2) reduced manufacture of Pampers not immediately needed by retailers, (3) fewer manufacturing orders that had to be “rushed” or “expedited,” and (4) lower inventories held by each company in the supply chain. The benefits of supply chain coordination at P&G have been so great that retailers such as Wal-Mart have contracted with P&G to manage Wal-Mart’s retail inventories on a just-in-time basis. This practice is called supplier- or vendor-managed inventory. Supply-chain management, however, has challenges in sharing accurate, timely, and relevant information about sales, inventory, and sales forecasts caused by problems of communication, trust, in