In December, the 20-city index ticked up 0.2 percent from the previous month, reversing November's small decline.
The S&P/Case-Shiller index covers roughly half of U.S. homes. It measures prices compared with those in January 2000 and creates a three-month moving average. The December figures are the latest available.
Despite the increases, prices nationwide are still about 30 percent below the peak they reached at the height of the housing bubble in the summer of 2006. They are now at the same level as in the fall of 2003.