Chairman and CEO, Humana The giant health insurer has executed well under McCallister and seems positioned to benefit from continued high health care spending. Like its competitors, Humana depends heavily on the federal government: More than 75% of revenues come from Medicare and other federal programs. Given how strapped the feds are these days, this suggests a fair amount of uncertainty for Humana. Even so, McAllister boosted sales by 9.5% over the past year, while profits are up nearly 11%. Investors noticed, driving the stock up by more than 35%.
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