Irrelevance of inflation: The Dow stocks

Abstract

The irrelevance of inflation is a proposition, inherited from corporate finance, which states that inflation is irrelevant for the valuation of nominal and real stock prices. In other terms, Net Present Values (NPVs) and stock returns are independent of the inflation rate.  The issue at stake is both theoretical and empirical, although the first came much before the latter. In the empirical realm, stock returns are found to be statistically negatively related to inflation. However, and theoretically, the classical school predicted that they should be related positively one-to-one. Moreover long run analysis, that came later, found that stock prices are positively related to price indexes. This stems from the fact that stocks are claims upon real assets, and, therefore, should be a hedge against inflation with the same one-to-one relation. This paper differs by subjecting all these hypotheses to the individual stocks included in the Dow Jones Industrial Index, and not to returns calculated from stock indexes, which is the usage. The empirical results in this paper support strongly the irrelevance of inflation.  This is true whatever the price index, whatever the econometric procedure, whatever the industry to which the stock belongs, and whatever the specification of the model.  Hence inflation is neither negatively nor positively related to stock returns, whether nominal or real.