Social expenditures in the U.S. were 19.2 percent of gross domestic product last year, up from 15.5 percent in 2005, according to data from the Organization for Economic Cooperation and Development.
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Still, the portion of GDP spent by the U.S. on social benefits last year was below the OECD average of 21.6 percent. The majority of member nations individually shelled out a higher percentage of GDP, as well.
Greenspan was the head of the U.S. central bank from 1987 to 2006. He declined to characterize the Fed's policy-making committee's assessment of the nation's economy after its most recent meeting Wednesday.
However, he noted that he sees a "strong and growing labor market" despite concerns about productivity growth.
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