U.S. house prices increased 0.4% in August, almost regaining the 0.7% revised decrease in July, but fell more than 2% from a year ago, according to the Federal Housing Finance Agency monthly House Price Index. Prices fell 2.4% in August from the year before and remain 13.6% below the peak in April 2007. In August, prices reached roughly the same point in the FHFA index measured in October 2004, heading up to the peak. The FHFA calculates is monthly index using purchase prices of houses backing mortgages sold to Fannie Mae and Freddie Mac. The FHFA has held those two companies in conservatorship since 2008. The analytics firm Clear Capital warned of possible new lows in prices heading into 2011 after sharp drops in October. The Standard & Poor’s/ Case-Shiller 20-city index for August showed a 1.7% increase from a year ago and a 0.2% drop from July. For the nine Census divisions measured by the FHFA index, prices ranged from a 0.6% decline in the Mountain Division to a 1.5% increase in the West South Central Division. Write to Jon Prior.