Stocks edged lower after a weak November manufacturing report heightened concern that the deadlock in Washington is hurting the economy. Factory output fell to its weakest level since July 2009, with the ISM index declining to 49.5 from 51.7. A reading below 50 indicates a contraction. Stocks had opened higher on news that manufacturing in China grew for the first time in 13 months and after Greece unveiled details of a bond-buyback program. December is historically the best month for stocks. The S&P 500 has advanced an average of 2% over the past 30 years during December, Schaeffer’s data show.