"...if you only look at the P/E ratio reported for any quarter or year, the ratio during peaks and troughs will be quite distorted when compared to the more stable long-term average. About every five years or so, the reported P/E will reflect the opposite signal in contrast to a more rational view of P/E valuations. For example, the reported value for P/E in early 2003 reflected a fairly high value of 32 just as the S&P 500 Index had plunged to 800 (E had cycled to a trough of $25 per share). A P/E of 32 generally screams "sell" to most investment professionals; yet, in early 2003, that was a false signal! A more rational view using one of the business cycle-adjusted methods reflected a more modest 18. In a relatively low inflation and low interest rate environment, the scream should have been "Buy"…

Several years later, in 2006 (after an unusually-strong run in earnings growth), E peaked at $82 per share as the S&P 500 Index was hesitating at 1500. Most market pundits were recommending a strong "buy" due to a calculated P/E of only 17. Yet, using the rational business cycle-adjusted methodologies, the true message was "STOP"—P/Es were saying sell, with P/E more than 25.

Well the pundits were actually (sort of) right—P/Es did expand… Yet it was due to (what should have been expected) the normal down-cycle in E rather than the pundit-promoted increase in the stock market. So when investors' stock market accounts were down almost 50%, they were handed explanations that the earnings decline was unexpected and the fault of the financial sector…

Many of the same pundits are bewildered by current market conditions and unsure about the future of E. The latest craze to extrapolate current conditions into the indefinite future has been named "The New Normal." Slow economic growth, high saving rates, and unstable financial conditions—all fairly typical at the end of a recession—are now basic assumptions for years into the recovery expansion. Maybe this time will actually be different…or maybe not…

As for the market and P/E, it's understandable that conservative investors and market spectators have watched the past six-month rally with awe. Yet the current P/E remains slightly undervalued and further gains are more likely; nonetheless, it is important to remain aware that typical market volatility makes it also likely that the market will experience significant short-term swings."