Current Shiller PE Ratio : 30.49 -0.34 (-1.12%)

Shiller PE ratio for the S&P 500.

Price earnings ratio is based on average inflation-adjusted earnings from the previous 10 years, known as the Cyclically Adjusted PE Ratio (CAPE Ratio), Shiller PE Ratio, or PE 10 — FAQ.

Data courtesy of Robert Shiller from his book, Irrational Exuberance .