Hussman: The Line Between Rational Speculation and Market Collapse

``The Shiller P/E (S&P 500 divided by the 10-year average of inflation-adjusted earnings) is now 27, versus a long-term historical norm of 15 prior to the late-1990's bubble. Importantly, the profit margin embedded into the Shiller P/E is currently 6.7% versus a historical norm of just 5.4%. ''