Beyond Tea Inc. wants to forecast sales of its menthol green tea. The company wants to use simple mean or a three period moving average forecast monthly sales. Given sales data for the past 10 months use both forecasting methods to forecast periods 7 to 10 and then evaluate each. Which method should they use? Use the selected method to make a forecast for month 11. Show all work. No Excel.
MONTH SALES
1 5
2 8
3 15
4 18
5 20
6 19
7 17
8 18
9 19
10 21