The financial crisis is over and the recession ended in 2009. But one of the federal government's biggest social welfare programs, which expanded when the economy convulsed, isn't shrinking back alongside the recovery.

Enrollment in the Supplemental Nutrition Assistance Program, as the modern-day food-stamp benefit is known, has soared 70% since 2008 to a record 47.8 million as of December 2012. Congressional budget analysts think participation will rise again this year and dip only slightly in coming years.

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