Home prices in the United States fell 5.9 percent in the second quarter from a year earlier, the biggest decline since 2009, as foreclosures added to the inventory of properties for sale, Bloomberg reported. Prices dropped 0.6 percent from the prior three months, the Federal Housing Finance Agency said today in a report. In June, prices retreated 4.3 percent from a year earlier, while increasing 0.9 percent from the previous month. Foreclosures are boosting the supply of properties on the market and undercutting the confidence of homebuyers, sapping demand even as mortgage rates tumble to the lowest levels in more than half a century. The U.S. inventory of homes for sale averaged 3.7 million during the second quarter, the highest number since the third quarter of 2010, data from the National Association of Realtors show.