U.S. consumer sentiment soared in December as Americans' outlook on the economy and job prospects improved, the University of Michigan reported Friday. The university's preliminary reading on overall consumer sentiment jumped to 82.5 in early December from the November final reading of 75.1. It was the highest reading since July and surpassed analyst forecasts for a reading of 76. "Nearly all of the improvement was concentrated in the economic outlook for the year ahead and in how consumers judged buying conditions," survey director Richard Curtin said in a statement. The survey's index of current economic conditions surged to 97.9 from 88 in November, while its measure of consumer expectations rose to 72.7 from 66.8. The current-conditions index was at its highest since July, while the consumer-expectations gauge was at its highest since August. Economists closely watch consumer-confidence indexes for clues on consumer spending, which accounts for 70 percent of U.S. economic activity.