 PHILADELPHIA--BUSINESS WIRE--Home prices across the United States rose in the first three months of the year at an annualized rate of 9.3 percent, according to Radian Home Price Index HPI data released today by Red Bell Real Estate, LLC, a Radian Group Inc. company NYSE: RDN. The company believes the Radian HPI is the most comprehensive and timely measure of U.S. housing market prices and conditions available in the market today. The Radian HPI also rose 8.8 percent year-over-year March 