COLUMBUS, Ga., March 16, 2012 /PRNewswire/ -- Aflac, the number one provider of supplemental insurance in the United States, serving more than 466,000 employers across the nation and protecting more than 50 million people worldwide, has once again been named a World's Most Ethical Company. This marks the sixth straight year that Aflac has appeared on this prestigious list compiled by Ethisphere® Institute, a leading international think-tank dedicated to the creation, advancement and sharing of best practices in business ethics, corporate social responsibility, anticorruption and sustainability. Aflac is the only insurance company that has maintained a spot on the list for six straight years, every year since the inception of the award.