Long-term U.S. mortgage rates fell this week, breaking a steady climb that pushed them to their highest levels in seven years. It was the first decline in four weeks in long-term loan rates amid the peak home buying season. Mortgage buyer Freddie Mac said the average rate on 30-year, fixed-rate mortgages was 4.56 percent, down from 4.66 percent last week. The average benchmark rate has been running at its highest levels since May 2011. By contrast, the 30-year rate averaged 3.94 percent a year ago.