Reversion to mean Shiller PE would take SPX down another 40% there is room to fall further, 27 >17:
Current Shiller PE Ratio: 27.04 -0.20 (-0.75%)
4:00 PM EDT, Mon Oct 10
Mean: 16.98
Median: 15.89
Min: 4.78 (Dec 1920)
Max: 44.19 (Dec 1999)
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