From the irrepressible mind of John Hussman, here:
Market conditions presently match those that have repeatedly preceded either market crashes or extended losses approaching 50% or more. Such losses have not always occurred immediately, but they have typically been significant enough to wipe out years of prior market gains. ... On the basis of historically reliable measures, the S&P 500 would have to move slightly below the 1000 level to raise its prospective returns to a historically normal 10% annually. ... Regardless of whether the market’s losses in this cycle turn out to be closer to 32% (which is the average run-of-the-mill bear market loss) or greater than 50% (which would be required to take historically reliable valuation measures to historical norms, though most bear markets have continued to undervalued levels), it’s going to be difficult to avoid steep losses without a plan of action. In our view, that action should be rather immediate even if the market’s losses are not. However uncomfortable it might be in the shorter-term, the historical evidence suggests that once overvalued, overbought, overbullish conditions become as extreme as they are today, it’s advisable to panic before everyone else does.
