Like many industrial nations over the last four decades, the Japanese economy has undergone a number of regime shifts, making parameter estimations difficult. One of the most significant shifts occurred in inflation in the mid 1970s as OPEC suddenly raised oil prices. This abrupt change likely caused consumers' expectations of future inflation to deviate significantly from realized (ex‐post) inflation. Using a Markov chain model, inflation forecasts that take into consideration changing regimes are employed to derive a unique set of real stationary variables that are likely to better represent consumers' expectations and are an alternative to the standard approach of adjusting nominal variables with ex‐post inflation. We employ these real variables in the consumption‐based capital asset pricing model (CCAPM). Estimates of the representative investor's coefficient of relative risk aversion (CRRA) are derived within the framework typically used to examine the equity premium puzzle. Our tests confirm that the equity premium puzzle, if it exists in Japan, is not as significant as previously thought.