A group of five large banks posted a 7.5 percent increase in mortgage-banking income in 2015 compared with the previous year, according to a new analysis by Inside Mortgage Trends. Officials at the banks pointed to a stronger housing market along with reduced servicing costs. Wells Fargo continued to lead the industry in terms of both mortgage-banking income and originations at the end of 2015. The bank had $6.50 billion in mortgage-banking income during the year ...