2.8.Methods of Forecasting Trend Seasonal Series Procedures: Draw the demand curves and estimate the season length N: Computer the moving average MA(N); Centralize the moving averages; Get the centralized MA values back on period; Calculate seasonal factors,and make sure of >c,=N Divide each observation by the appropriate seasonal factor to obtain the deseasonalized demand .Forecast is made based on deseasonalized demand. Final forecast is obtained by multiplying the forecast(with no seasonality)with seasonal factors.2.8. Methods of Forecasting Trend Seasonal Series Procedures: • Draw the demand curves and estimate the season length N; • Computer the moving average MA(N); • Centralize the moving averages; • Get the centralized MA values back on period; • Calculate seasonal factors, and make sure of  ct=N. • Divide each observation by the appropriate seasonal factor to obtain the deseasonalized demand • Forecast is made based on deseasonalized demand. • Final forecast is obtained by multiplying the forecast (with no seasonality) with seasonal factors