CHATTANOOGA, TN (Times Free Press) -- Tennessee's biggest health insurer helped ensure its own fiscal health last year by boosting net income by more than 26 percent and swelling its reserves to more than 50 percent above what is legally required.

BlueCross BlueShield of Tennessee, the state's biggest nonprofit corporation with $5.6 billion in annual revenues, said Monday it earned record profits of $221.5 million during 2012.

Even with its income gain last year, BlueCross officials said the 4 percent profit margin was still the lowest among the major health insurers operating in Tennessee.

"As a tax-paying, not-for-profit company we can operate on a lower profit margin than the investor-owned companies in our industry, but we still try to maintain a small profit margin to ensure we can continue to serve our customers and remain financially strong," BlueCross Vice President Roy Vaughn said. "I think our customers want us to be strong financially and to do well so that they know they can depend upon our services."

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