An experienced purchase manager feels that moving average method would be most appropriate to make weekly sales forecasts of company’s main product. The manager has historical data of sales forecasts and actual sales for last 100 weeks of company’s main product. Explain how should the manager determine the number of moving periods he should use to make the forecasts- that is, should he use 2-period, or 3-period, or 4-period, or 5-period, etc., moving average. Use your own dataset to explain.