Stocks moved lower Monday, but closed off their session lows. The Dow Jones industrial average lost 0.4%, the S&P 500 0.3% and the Nasdaq 0.1%. Volume increased from Friday's level on the NYSE, but decreased on the Nasdaq, according to preliminary data. On Tuesday, Alcoa (AA) is slated to kick off fourth-quarter earnings season with its report. Wall Street expects the aluminum giant to swing to a profit of 6 cents a share, while revenue declines