Authors aim is to propose a particular methodology to be used to regard seasonal fluctuations on balancing time series while using artificial neural networks based on the example ofimports from the People's Republic of China (PRC) to the USA(US). The difficulty of forecasting the volume of foreign trade is usually given by the limitations of many conventional forecasting models. For the improvement of forecasting it is necessary topropose an approach that would hybridize econometric models and artificial intelligence models.