WASHINGTON -- In a sign that further weakening may be in store for the U.S. housing market, an index of sales contracts on previously owned U.S. homes fell 4% in November from the prior month, the National Association of Realtors reported Tuesday. The index, which is considered a leading indicator of existing home sales, was down 5.3% from the prior year. Pending home sales in November fell in all four regions, with declines of 7.2% in the Northeast, 6.7% in the Midwest, 2.4% in the West and 2.2% in the South. The October pending home sales index was revised to a decline of 4.2% from a prior estimate of a 0.7% drop. NAR is calling for a real-estate focused stimulus plan from the government.