Banks and thrifts reported a sharp increase in the volume of home loans sold in their mortgage banking operations last year, hitting the highest level since 2009, according to a new Inside Mortgage Trends analysis of bank call report data. Mortgage banking units generated $1.553 trillion in loan sales during 2012, a 36.9 percent jump from the previous year. Activity peaked at $417.1 billion in the fourth quarter, a 3.9 percent increase over the third quarter. Some double counting ... [Includes one data chart]