Mortgage banking remained hugely profitable during the fourth quarter of 2012, but it took a rebound in servicing income to boost overall earnings, according to the most recent quarterly performance report from the Mortgage Bankers Association. The MBA data show that average pretax income for a wide variety of mortgage companies rose 11.1 percent from the third to the fourth quarter of last year, hitting a record $4.71 million. That raised the average firm’s pretax income for all of 2012 to ...