Sales of new U.S single-family homes rose 7.1% in August, according to the Commerce Department, a much larger increase than the 3.5% jump forecast by economists in a Reuters survey. Sales were also up 18% from the previous year. New home sales increased to a seasonally adjusted annual rate of 713,000 units last month, up from 666,000 in July. The biggest jumps in sales were in the South and West and were likely aided by lower mortgage interest rates.