Futures off ahead of factory, home price data

NEW YORK (Reuters) - Stock index futures were lower on Tuesday as investors found little reason to make big bets in what was expected to be a light-volume session following the previous week's gains. The S&P 500 has risen for four straight sessions and turned positive for the year on Friday. Improving economic data helped boost equities last week. The gains were amplified by the light pre-holiday trading. Investors looked ahead to November Midwest manufacturing data, scheduled for release at 8:30 a.m. EST as well as S&P/Case-Shiller home price data for October due at 9 a.m. ...