YTD stock performance: 56%
Market cap: $13.8 billion
Fortune 500 Rank: 79
As the second-largest provider of Medicare's managed care plans in the United States, Humana is well positioned to take advantage of the flood of baby boomer retirees.
Roughly 1.9 million Americans are covered by its Medicare Advantage health insurance plans already.
New retirees are already boosting the company's revenues and profitability. Humana reported an 11% jump in third quarter revenue and boosted its 2012 earnings-per-share outlook by roughly 56% after enrollment outpaced the company's earlier forecasts.
Like other companies in the managed care sector, Humana's stock took a hit between 2008 and 2010 as investors feared the effects of health care reform. As the broad outlines of health care reform looked less punitive than expected for managed care companies, investors spent 2011 racing back into the sector.
The company will be undergoing a management shift in the next year. Chief Executive Michael McCallister plans to retire after a decade of serving at the firm's helm.
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