If it's November, it must be time for the annual year-end rally in the U.S. stock market.

That's certainly the way the script played out in 2004, when the Standard & Poor's 500-stock index, up a mere 3 percent through the first 10 months, came on strong to finish the year with an 11 percent total return, including dividends.

That display of enthusiasm after a long spell of sluggishness prompted more than a few sages to invoke the investment adage, "Never sell a dull market short."

Wouldn't you know, the U.S. market has been dull again in 2005, with the S&P 500-stock index down 1.1 percent and the Dow Jones industrial average down 3.5 percent for the year through Oct. 28. At no point in 2005 has the total return of either average showed a net gain or loss since New Year Day's of more than 7 percent.

In most other parts of the world, stock markets have made solid gains. The Dow Jones Stoxx 50 index of large European stocks, for example, has jumped 13 percent, and the Nikkei 225 index in Japan has gained 16 percent.

U.S. stocks have been dogged by concerns that ranged from hurricanes Katrina and Rita to a steady barrage of increases in short-term interest rates by the Federal Reserve.

That invites the question: Is the aphorism valid? Are dull periods in stocks reliable precursors of rallies? To put the pattern to a simple test, I looked at the 10 previous years since 1945 in which the S&P 500, measured by price change only, rose or fell less than 5 percent -- and what happened in the years that came next.

For example, a 1.5 percent drop in 1994 was followed by a 34 percent jump in 1995. After a 2 percent gain in 1987, the index returned 12 percent in 1988. And so forth.

Let's acknowledge that it's inaccurate to label all those years of small net changes "dull." Anyone who was investing in 1987 will recall that the year included gains of about 40 percent through late August, followed by declines of about 35 percent in less than two months. The market crashed.

Allowing for such anomalies, the statistics still tell an interesting story. The past seven "dull" years were all followed by much better performances, with gains averaging 18 percent.

Further back, in the 1940s and '50s, none of that magic was on display. The dull year 1956, with a gain of 2.6 percent, was followed by a 14 percent decline in 1957. The dull year 1947, when the index finished unchanged, segued into another dull year in 1948, when it slipped 0.6 percent.

Truly patient people of that time were rewarded with gains of 10 percent or more in each of the next four years, 1949 through 1952. It took nerve to practice such patience, what with all the hard experience of the '30s and early '40s still fresh in everybody's mind.

So the record shows there is nothing automatic about a good year after a dull year. This is a helpful point to keep in mind, given that "sure things" in stocks are always suspect. The market is never under any obligation to repeat its history.

Even so, there are good things to be said about do-nothing years. When the economy is growing strongly, a dull year in stocks gives the market time to work off whatever excesses of enthusiasm may have built up. Also, it allows corporate earnings, the basic underpinning for stocks, a chance to catch up.

The net gain for the S&P in the years after all 10 dull years we have looked at averages 11 percent, before dividends are counted in.

It's a new century now, and a new and different world economy, with no guarantees of what all that will mean. Still, on balance over the past six decades, it has proved to be reasonable to consider buying stocks in years when the U.S. market isn't going anywhere.