Seasonal integration and Japanese aggregate data

The presence of seasonal integration in Japanese macro data is tested. The targeted variables are real values and deflators for GDP, consumption, inve stment, government expenditure, exports, and imports. First, with respect t o seasonality, an entirely different conclusion is obtained for the real va lues and the deflators of the data series examined. Second, it is clear tha t there is a difference between the analytical results obtained when a stru ctural break is considered and those obtained when a structural break is no t considered.