Kommer börsen att rasa nu? Dags att dra sig ur?

Here's how I see the odds. The chances are about one in three that we suffer a huge, wrenching correction in the next year or two similar to the one in 1987. That possibility is so high because stocks are so startlingly expensive. Another high probability event is that markets go on a long sideways grind, with smaller drops along the way. What's extremely unlikely is that the market rises substantially from current levels and stays there for any extended period.

Whatever happens in the next couple of years, the odds are overwhelming that investors who buy stocks today will reap puny returns for 10 years. For example, if you'd purchased shares at today's PE of 22 in early 2003, you would have gotten a return of around 3% a year, barely enough to compensate for inflation, let alone buy the blood pressure medication you'd need to survive the scary ride of stock ownership.

Now let's look out a decade or two. The evidence is extremely strong that price matters, and matters a lot: except in rare cases, buying stocks when they are pricey -- when the Shiller PE exceeds 20 -- leads to puny returns ten years later.

Not that you'd ever know that from the happy talk from Wall Street. So screen the noise out, and follow the numbers. They'll eventually get better for investors. But to get back there, we may revisit October of 1987.