Can Earnings Innovations Explain the Inverse Relationship Between Unanticipated Inflation and Stock Returns?

Hooks [1991] argues that the explanatory power of unanticipated inflation in stock return models appears to result from the relationship of unanticipated inflation with the earnings capitalization rate and not the impact inflation has on the level or growth rate of earnings. Here we extend this line of investigation by examining the relationship between unanticipated inflation and the earnings innovation extracted from a univariate earnings forecast. We show that unanticipated inflation has no significant relationship with innovations in conventional earnings. However, we find that unanticipated inflation has a significant positive relationship with the magnitude of the earnings innovation during the 1955-85 period when earnings are adjusted to account for the effects of inflation on firms' assets and liabilities.