A new approach to examining the sustainability of external imbalances: the case of Japan

This study aims to solve the puzzle of the conventional practice of examining the sustainability of external accounts by initially looking for cointegration between imports and exports. This study proposes a new approach to examine this thesis using unit root tests (with unknown break date) on trade balance series rather than testing the cointegration relationships between imports and exports. In contrast to previous findings, this study has shown empirically that Japan's trade balances are unsustainable. This finding has important policy implications for Japan's external accounts.