Most banks that have reported second-quarter earnings said their mortgage banking income declined from the first three months of 2013, but profitability remained strong, according to a new Inside Mortgage Trends analysis of corporate disclosures. A group of 15 banks that includes most of the top depository institutions in the mortgage business reported a combined $6.72 billion in mortgage banking income during the second quarter of 2013. That was up 5.0 percent from the earnings ... [Includes one data chart]