Futures slump as oil prices fall further

* Oil prices were down about 3 percent as hopes for a deal between OPEC and Russia on output cuts faded with Goldman Sachs saying it was "highly unlikely". * Investors were also concerned about a China-led global economic slowdown and the pace of rate hikes by the U.S. Federal Reserve. * Adding to concerns, consumer saving from cheap gasoline prices have failed to translate into higher spending as U.S. consumers increase their savings and choose to pay down debt rather than buy big-ticket items.