If there's one thing for investors to be thankful for this year, it's the turnaround we've seen in the stock market in 2009. From the depths of despair, the market has managed to gain back a huge chunk of its big declines during the last bear market. Since Thanksgiving became an official federal holiday (1941), the S&P 500 has been up 20% or more through Thanksgiving 16 times, and this year is one of them. With a year-to-date gain of 22.72%, the S&P 500 is having its best year heading into Thanksgiving since 1997 when the index was up 28.47%. As shown, the average change for the rest of the year when the S&P 500 has been up 20% or more through Thanksgiving has been 1.96%, with positive returns 10 out of 15 times. Happy Thanksgiving!