Finance and Financial Management Commons^™

P/E Changes: Some New Results, Thomas S. Zorn, Donna M. Dudney, Benjamas Jirasakuldech

Department of Finance: Faculty Publications

The P/E ratio is often used as a metric to compare individual stocks and the market as a whole relative to historical valuations. We examine the factors that affect changes in the inverse of the P/E ratio (E/P) over time in the broad market (S&P 500 Index). Our model includes variables that measure investor beliefs and changes in tax rates and shows that these variables are important factors affecting the P/E ratio. We extend prior work by correcting for the presence of a long-run relation between variables included in the model. As frequently conjectured, changes in the P/E ratio have …