الملخص

Abstract This paper deals with the treatment of trend seasonality of time series by using the method of exponential smoothing, indeed the triple exponential method (Winter's Method) which includes two procedures of analysis, the first one is (multiplicative seasonal model) and second (additive seasonal model), we conclude the forecasting for future data for multiplicative model is better than additive model by using many criterions .MAD, MAPE, MSE.