Improvement in U.S. consumer sentiment stalled at the end of November as uncertainty grew over federal tax and spending programs next year, the University of Michigan reported Wednesday. The university's final consumer-sentiment reading this month rose slightly to 82.7 from 82.6 in October but was down from an early-November reading of 84.9. “The late-month retreat was accompanied by more economic uncertainty about future federal taxes and spending programs and the inability of the political parties to reach a settlement," survey director Richard Curtin said in a statement. The survey's gauge of current economic conditions rose to 90.7 this month from 88.1 in October, and the index of consumer expectations fell to 77.6 in November from 79.0 the previous month. Economists closely watch consumer-confidence readings for clues on consumer spending, which accounts for about 70 percent of U.S. economic activity.