1. The demand for CP's gardening tools from consumers is highly seasonal,
2. peaking in the spring as people plant their gardens. This seasonal demand
3. ripples up the supply chain from the retailer to CP, the manufacturer. CP has
4. decided to use aggregate planning to overcome the obstacle of seasonal
5. demand and maximize profits. The options CP has for handling the seasonality
6. are adding workers during the peak season, subcontracting out some of the
7. work, building up inventory during the slow months, or building up a backlog of
8. orders that will be delivered late to customers. To determine how to best use
9. these options through an aggregate plan, CP's vice president of supply chain
10. starts with the first task—building a demand forecast. Although CP could
11. attempt to forecast this demand itself, a much more accurate forecast comes
12. from a collaborative process used by both CP and its retailers to produce the
13. forecast shown in Table 1.
14. CP sells each tool to the retailers for $40.
15. The company has a starting inventory in January of 1,000 tools.
16. At the beginning of January the company has a workforce of 80 employees.
17. The plant has a total of 20 working days in each month, and
18. each employee earns $4 per hour regular time.
19. Each employee works eight hours per day on straight time and the rest on overtime.
20. As discussed previously, the capacity of the production operation is determined primarily by the total labor hours worked.
21. Therefore, machine capacity does not limit the capacity of the production operation.
22. Because of labor rules, no employee works more than 10 hours of overtime per month.
23. Currently, CP has no limits on subcontracting, inventories, and stock-outs/backlog.
24. All stockouts are backlogged and supplied from the following months' production.
25. Inventory costs are incurred on the ending inventory in the month.
26. The various costs are shown in Table 2.