You can use the sales forecasting starter workbook without modification for many sales forecasts. However, you might want to change the workbook so that it more closely matches your requirements. For example, you can add text that describes the product being manufactured or purchased and for which sales are forecasted. You can also increase or decrease the number of periods. For example, you can increase the number of periods to 12 if your periods are months and you want to forecast an entire year.
Note: Before you change anything in the starter workbook other than the Sales Forecast Inputs schedule, unprotect the document.
To increase the number of periods, remove the borders from the last column; then copy the current last column to the right as needed. To decrease the number of periods, simply delete any unneeded column from the right side of the schedule. When you finish these steps, you can replace the borders on the right and reinstate cell protection as needed.