Bank of Japan updates seasonal adjustment methodology for balance of payments statistics using revised 1996-2025 data and new forecasting models.
The Bank of Japan has revised seasonally adjusted data for major current account items in its Balance of Payments Statistics, effective May 13, 2026. The update incorporates historical data from January 1996 to December 2025, aligned with the BPM6 manual, and introduces predicted seasonal factors for 2026 onward.
The revision uses the U.S. Census Bureau’s X-12-ARIMA model with default settings for outlier detection and a logarithmic transformation for most series. ARIMA forecasts extend up to 48 months, while backcasting remains unused. Direct investment income is excluded from the multiplicative model adjustments.
No immediate market reaction was specified in the release. The changes aim to improve accuracy in tracking Japan’s external economic transactions.