It didn’t take much to bring borrowers back to the refinance table. Just a slight drop in interest rates pushed refinance applications higher after they had fallen for the last month. That helped increase total mortgage application volume 3.6 percent for the week, according to the Mortgage Bankers Association, whose seasonally adjusted results included an accommodation for the Columbus Day holiday. Volume was nearly 19 percent below the same week a year ago, when interest rates were lower. Applications to refinance a home loan rose 3 percent last week but were still nearly 36 percent lower than the same week one year ago.