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Question
NARRBEGIN: SA_89_91The number of employees on the payroll at a computer software company is recorded at the start of each month from January 2007 to December 2009. These data are shown below.
| Year | Jan | Feb | March | April | May | June | July | Aug. | Sept. | Oct. | Nov. | Dec |
| 2007 | 348 | 352 | 330 | 347 | 339 | 370 | 380 | 392 | 400 | 410 | 405 | 367 |
| 2008 | 350 | 341 | 345 | 355 | 342 | 350 | 370 | 395 | 410 | 401 | 405 | 365 |
| 2009 | 348 | 349 | 350 | 350 | 342 | 377 | 369 | 400 | 410 | 406 | 400 | 370 |
Use the method of moving averages with an appropriate span to forecast retail sales for 2010. Do you obtain a good fit? Do you have confidence in your forecast? Explain your answers.
Answer
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NARRBEGIN: SA_79_80
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