Inflation expectations are one of the most essential components of monetary policy decisions. Upon examining Japanese inflation expectations between 1991:Q4 and 2025:Q1, we propose a modified empirical model that includes a forecast trend term in addition to the forecast revision term. The forecast trend term affects the forecast errors. In addition, we find evidence that consumption tax hikes affected the forecast errors, partly due to the uncertainty of actual implementation in the future. The full sample results indicate that people in Japan form non-rational expectations with information rigidity. However, this holds only in the recent episode of inflation following the post-COVID period. During the zero-inflation periods, people formed rational expectations without information rigidity, but with the possibility of deviating from rational expectations.