Commentators note that U.S. investors have poured a lot of money into foreign stock markets in recent few years.

As it happens, the flow hasn't been just one way.

In fact, based on cumulative 12-month totals derived from monthly Treasury Department data, foreigners appear to have invested a record amount in U.S. corporate stocks during the period ending in July, the latest month available.

When was the last record set? In January 2001, just as the dot-com bubble was bursting and the bottom was falling out of U.S. share prices.

Over the past decade, foreigner investors' buying and selling behavior has proved to be a reasonably good long-term timing signal -- in contrarian terms, that is.

In 2002, for instance, when the S&P 500 index began a major upside run, foreigners kept their investment to a minimum for nearly three years. They eventually rejoined the bullish party in late 2005.

A cynic might wonder: now that they have really started piling in, can much lower prices be far behind?

Michael Panzner is a 25-year veteran of the global stock, bond, and currency markets and the author of Financial Armageddon: Protecting Your Future from Four Impending Catastrophes and The New Laws of the Stock Market Jungle.