The file Pharmaceutical Sales.xlsx contains quarterly sales data for a large pharmaceutical company from first quarter 1998 through fourth quarter 2007 (in millions of dollars). The time series plot...

The file Pharmaceutical Sales.xlsx contains quarterly sales data for a large pharmaceutical company from first quarter 1998 through fourth quarter 2007 (in millions of dollars). The time series plot in Figure 16.35 indicates a fairly consistent upward trend, with a relatively small amount of noise. Can Holt’s method be used to provide reasonably accurate forecasts of this series?

Objective To use Holt’s exponential smoothing model to track the trend in the pharmaceutical company’s quarterly sales data.