Overall, according to the Congressional Budget Office, macroeconomic trends account for 65% of the increased spending in the food stamp program. A combination of higher food prices and lower beneficiary incomes accounts for an additional 15%. The temporary increase in benefits included in the 2009 stimulus bill accounts for the remaining 20%, and that increase ended as of Nov. 1. Over the next decade, according to CBO economic projections, the number of food-stamp beneficiaries will fall by about 30%, to 34.3 million. Annual outlays will fall by $10 billion in current dollars, and much more when inflation is taken into account.

So what is the fight about? Congressional and other critics of the program complain that standards are lax and that only individuals at or below the poverty line should be eligible. Even if this argument were accepted, CBO calculates, outlays would fall by only 4%. Second, say the critics, too many individuals become eligible “categorically” through their participation in other programs rather than through income tests. This is another distinction that doesn’t make much of a practical difference: Eliminating categorical eligibility outright would reduce the number of beneficiaries by only 4% and outlays by only 2%.