WASHINGTON (AP) - Consumers shrugged off the 16-day partial government shutdown and spent more on autos, clothing and furniture in October, pushing U.S. retail sales up by the largest amount in four months. The Commerce Department says retail sales rose 0.4 percent in October, up from a flat reading in September. Sales were held back by a steep drop in gas prices. Excluding sales at gas stations, retail spending increased an even stronger 0.5 percent. And core sales, a category that excludes volatile spending on autos, building supplies and gas, also rose 0.5 percent, up from a 0.3 percent gain in September. The October retail sales indicate that consumers stepped up spending at the start of the October-December quarter. Their spending accounts for 70 percent of economic activity.