Stock rally at start of 2010 augurs well _ maybe

If the stock market holds to a pattern it has followed for most of the past 40 years, 2010 could be a big year for investors.

Since 1973, a big advance on the first trading day of January has been a strong sign stocks will post robust gains for the rest of the year.

On Monday, upbeat news about manufacturing lifted the Dow Jones industrial average 155 points, or 1.5 percent. The Standard & Poor's 500 index rose 17 points, or 1.6 percent.

When the S&P 500 has gained more than 1 percent on the first day of trading, the index has ended the year higher 86 percent of the time, according to Schaeffer's Investment Research.

After a big …