Shiller PE Ratio (CAPE ratio)

The CAPE ratio is a valuation measure that uses real earnings per share (EPS) over a 10-year period to smooth out fluctuations in corporate profits that occur over different periods of a business cycle. The CAPE ratio, using the acronym for cyclically adjusted price-to-earnings ratio, was popularized by Yale University professor Robert Shiller. It is also known as the Shiller P/E ratio. The P/E ratio is a valuation metric that measures a stock’s price relative to the company’s earnings per share. EPS is a company’s profit divided by the outstanding equity shares. The ratio is generally applied to broad equity indices to assess whether the market is undervalued or overvalued. While the CAPE ratio is a popular and widely-followed measure, several leading industry practitioners have called into question its utility as a predictor of future stock market returns.