NEW YORK | Mon Oct 31, 2011 5:27am EDT

NEW YORK (Reuters) - Stock index futures pointed to a weaker open for equities on Wall Street on Monday, with futures for the S&P 500, the Dow Jones and the Nasdaq 100 down by between 0.6 and 0.9 percent.

The Institute for Supply Management-New York releases the October index of regional business activity at 8:30 a.m. EDT. In September, the index read 538.0.

The Dow Jones industrial average finance/markets/index?symbol=us%21dji">.DJI gained 22.56 points, or 0.18 percent, to 12,231.11. The Standard & Poor's 500 Index .SPX.INX added 0.49 point, or 0.04 percent, to 1,285.08. The Nasdaq Composite Index .IXIC shed 1.48 points, or 0.05 percent, to 2,737.15