WASHINGTON (9/3/15)--The Federal Deposit Insurance Corp. (FDIC) reported Wednesday that U.S. banking earnings jumped 7.3% on an annual basis in the second quarter to $43 billion. The increase was fueled by healthier revenues and slimmer noninterest expenses (American Banker Sept. 2). Revenue rose by 2.1% annually, buoyed by a 5.4% climb in loan growth. Quarterly, meanwhile, loan growth accelerated by 2.2%, or $185 billion. Still, low interest rates continue to press down on overall earnings, according to American Banker. On an annual basis, bank net-interest margins declined slightly to 3.06% from 3.15% during the quarter. “The interest-rate environment remains challenging for banks,” said Martin Gruenberg, FDIC chair. “Revenue growth has been modest and net-interest margins continued to decline, even as banks extended asset maturities to mitigate the impact of low rates” …