Confidence among U.S. consumers unexpectedly fell in December, restrained by concern that jobs will remain scarce in 2011.

The Conference Board reported Tuesday that its Consumer Confidence Index unexpectedly fell to 52.5 from 54.3 in November. Another report showed home values dropped more than economists projected.

The loss of confidence is at odds with a separate survey by the University of Michigan that showed sentiment improved to a six-month high in December, and with data showing holiday spending posted the biggest gain in five years.

Federal Reserve policymakers this month said "depressed" housing and high unemployment remained constraints on consumer spending, supporting their plans to expand monetary stimulus.

"We should watch what consumers do and not what they say," said Omair Sharif, an economist at RBS Securities Inc. in Stamford, Conn. "If you looked at the confidence data, you wouldn't have looked for the pace of spending to accelerate as much as it has."

But he noted that consumers remained cautious and nervous about the direction of the job market.

The median forecast for the Conference Board's index, based on a survey of 61 economists, projected it would increase to 56.3. The index averaged 96.8 during the last economic expansion that ended in December 2007.

"The fact confidence moved lower is a bit surprising given the other data we have observed for the month," said Dean Maki, chief U.S. economist at Barclays Capital Inc. in New York. "Month-to-month changes in confidence are not well correlated with those in spending. Reports from retailers as well as data on spending have been upbeat. We would give those more weight."

The S&P/Case-Shiller index of property values fell 0.8 percent in October from the same month in 2009, the biggest year-over-year decline since December of last year, the group said. The index measures prices in 20 U.S. metropolitan areas. Philadelphia is not among them.

"Despite the fact that housing will remain at pretty low levels through next year, economic growth in general will be fairly robust," said Maki.

The home-price gauge fell 1 percent in October from the prior month after adjusting for seasonal variations, matching September's drop, which was larger than previously estimated.

Eighteen of 20 cities had a decrease in prices in October, led by a 2.1 percent drop in Atlanta, and drops of 1.8 percent each in Chicago and Minneapolis. Denver and Washington posted gains.

Six markets - Atlanta, Charlotte, Miami, Seattle, Tampa, and Portland, Ore. - reached their lowest levels in October since prices started to retreat in 2006.