An Investigation into the Causes of Stock Market Return Deviations from Real Earnings Yields

Abstract

This research demonstrates that the simple difference between the current earnings yield on the S&P500 and the long-term real TIPS yield has significant forecasting power for excess returns on that stock market index over both short-term and long-term investment horizons. For all time frames, deviations from that theoretical identity for the equity premium are positively related to current economic slack in the economy. Over annual horizons, those excess stock return deviations are negatively (positively) associated with recent inflation rates (money growth). Inflation is found to be positively (negatively) related to monetary policy restrictiveness (long-term real profit growth) in the future.

Keywords: equity premium, stock market returns, inflation, monetary policy, output gap, profit growth