Five years after the banking crisis, Federal Deposit Insurance Corp. Chairperson Martin Gruenberg is growing optimistic on improving credit quality, falling delinquencies and rising loan balances.

Annual income for the banking industry hit $141 billion in 2012, the highest level since 2006, Gruenberg said while speaking to the 2013 Independent Community Bankers Association National Convention.

Borrower credit quality improved over the past 10 consecutive quarters, while delinquent loans and charge-offs declined, Gruenberg said.

Loan balances also grew, increasing by $120 billion in just the fourth quarter of 2012.

"The largest single category for growth was in commercial and industrial lending, but we also saw increases in consumer loans, farm loans, and even real estate loans," Gruenberg pointed out.

"These positive trends have been broadly shared across the industry, among large institutions, mid-size institutions, and community banks. So I think it is fair to say that we continue to see a gradual but steady recovery in the U.S. banking industry that has now been sustained over three years," Gruenberg added.

Bank failures also are less common. In the wake of the financial crisis, the FDIC recorded 157 bank failures in 2010. That figure dropped to 92 bank failures in 2011 and 51 last year.