Home prices rose in August at their fastest since February 2006 and hit an all-time high in Dallas-Fort Worth, according to the latest Standard & Poor’s/Case-Shiller 20-city home price index.Still, across the U.S., price gains slowed in many cities from July, a sign that the spike in prices over the past year may have peaked. U.S. prices rose 12.8 percent over the 12 months ending in August and 9 percent in DFW. All 20 cities showed year-over-year gains. However, a measure of month-over-month prices for the 20 cities rose just 1.3 percent in August. That’s down from a 1.8 percent month-over-month gain in July. And 16 of the 20 cities reported more modest price increases in August than July. Greater demand and a tighter supply of homes for sale have helped drive prices higher over the past year. But over the summer, mortgage rates jumped from their record lows. And weaker job growth is discouraging potential home buyers. In addition to DFW, prices in Denver hit record levels in August. None of the other cities have returned to where they were before the real estate collapse. Average home prices are only back to mid-2004 levels and 22 percent below their April 2006 peak. “Denver and Dallas again set new highs,” David Blitzer, chairman of the Index Committee at S&P Dow Jones Indices, said in a statement. “All the other cities remain below their peaks.”Laurie Brants, co-owner and agent with Brants Realtors in Fort Worth, said some neighborhoods are seeing strong price gains, but not all. Though Tuesday’s Case Shiller report is positive for the market, it’s too early yet to call the local home market fully recovered, she said. “The market is better,” Brants said. “We’ve had a great recovery. There’s still reluctance to jump in wholeheartedly.” DFW home prices are 32 percent higher than they were in January 2000, according to the report. Area home prices peaked around August 2006 but began tumbling in August 2008. Prices started rising sharply in March, according to Case Shiller. In Las Vegas, prices rose 29.2 percent from a year earlier, the fastest in the nation. But they’re still 47 percent lower than they were before the housing market collapsed. Many cities on the index are seeing their gains slow, the report shows.Prices in San Francisco increased 0.9 percent in August, down from a 2.2 percent monthly increase in July. Ellen Haberle, an economist with the national real estate brokerage Redfin, said that prices have been driven higher by a limited supply of houses on the market. She expects home sales to fall in September and October partly because the federal government shutdown likely scared off potential home buyers. Contingent Macro Advisors economists Maninder Sibia and Steven Wood said housing inventory was only 83 percent of normal levels. They expect the supply to increase as rising prices encourage home owners to put their houses on the market. Staff writer Sandra Baker contributed to this report, which includes material from The Associated Press.