The biggest one-week rate drop in a decade unleashed a run on refinances last week, although it did not especially spur spring buyers. Mortgage application volume surged 18.6 percent from the previous week and 28 percent from a year ago, according to the Mortgage Bankers Association’s seasonally adjusted index. Refinance applications jumped 39 percent for the week to the highest level since January 2016. Volume was 58 percent higher than a year ago, when interest rates were higher. The average contract interest rate for 30-year fixed-rate mortgages with conforming loan balances ($484,350 or less) decreased to 4.36 ... (full story)