ML-Implode News - Hussman: Valuations Not Only Mean-Revert; They Mean-Invert

Investors should expect market overvaluation or undervaluation to be reliably "worked off" within a period of about 12 years, on average. That's mean-reversion, but that's not where the process ends. Rather, the valuation extremes of the market tend to be fully inverted over a horizon of about 18-21 years; ending with extremes of the same degree but in the opposite direction. That's what we'll call "mean-inversion." Statistically, a period of somewhere close to two decades has typically stood between the wildest exuberance and the deepest despair on Wall Street, and vice-versa. Valuations remain on the wildly exuberant side here.
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The 2009 low is often discussed as a "secular" valuation trough. It didn't even come close. While I did emphasize after the 2008 plunge that stocks had become undervalued relative to historical norms, remember that valuations similar to the 2009 trough were followed, in the Depression, by a further two-thirds loss in the value of the stock market. The market would have had to decline by an additional 50% to match the valuations observed at prior secular lows

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Hussman: Valuations Not Only Mean-Revert; They Mean-Invert