Mortgage activity down 13.5 percent, refinancing off 20 percent 11 (UPI) -- U.S. mortgage activity dropped sharply in the week as interest rates on a variety of long-term loans rose, the Mortgage Bankers Association said Wednesday. Mortgage applications fell by 13.5 percent on an unadjusted basis in the week that ended Friday, the MBA said. The MBA said refinancing activity fell by 20 percent from the previous week. Average interest rates for 30-year, fixed-rate loans with balances under $417,500, rose from 4.73 to 4.8 percent with points rising from 0.33 to 0.46 in the week. Interest rates for jumbo loans -- those $417,500 or larger -- increased from 4.71 percent to 4.84 percent, with points climbing from 0.25 to 0.41. Average interest rates on 30-year, fixed-rate mortgages backed by the Federal Housing Administration rose from 4.48 percent to 4.56 percent with points rising from 0.03 to 0.28. The average interest rate for 15-year, fixed-rate loans increased from 3.75 percent to 3.83 percent with points rising from 0.3 to 0.42. For short-term adjustable rate loans, the average interest rate rose from 3.49 percent to 3.59 percent with points shifting from 0.37 to 0.43.