The U.S. stock market rallied on Monday as the session marked the one year anniversary of the 2009 market bottom. 

Headlines were devoid of significant economic data and earnings reports as the S&P 500 Index rose 3.16 points, or 0.28 percent, to trade at 1,141.66 at 2:56 pm. The Dow Jones Industrial Average is up 24.56 percent, or 0.23 points, to trade at 10,577.08. Both indices reached their 2009 lows on the same day.

The transportation sector leads the stock market, with the Dow Jones Transportation Average up 1.50 percent.  Railroads are trading up as Union Pacific (NYSE:UNP) is up 2.49 percent and Norfolk Southern (NYSE:NSC) is up 1.53 percent.

Airlines are also among the best performers as Delta Air Lines (NYSE:DAL) gained 3.67 percent and Southwestern Airlines (NYSE:LUV) gained 2.15 percent.

On March 9, 2009 the S&P 500 closed at a low of 676.53.  Since then, the index has rallied about 70 percent.

Although there is still the possibility of a double dip recession, investors have reasons to be optimistic because bull markets usually last at least two years. 

According to USA Today, the last time it lasted less than two years was in 1947.  The last time a bull market lasted less than a year was during the Great Depression.