WASHINGTON (AP) – Average long-term U.S. mortgage rates fell for the fifth straight week amid volatility in world financial markets. Mortgage buyer Freddie Mac says the average rate on a 30-year fixed-rate mortgage slid to 3.72 percent this week, down from 3.79 percent last week and the lowest since it averaged 3.68 percent in April 2015. The average rate on a 15-year fixed-rate mortgage slid to 3.01 percent from 3.07 percent last week. Mortgage rates have continued to fall despite the Federal Reserve’s decision in December to raise the short-term rate it controls for the first time since 2006. Global markets have been rattled this year by signs of a global slowdown and big drops in the price of commodities, including oil. Investors have sought refuge in U.S. Treasurys, pushing down long-term U.S. rates.