The cost of food stamps has increased in recent years as more people join the program, which will continue to expand through at least 2014, according to a Congressional Budget Office (CBO) report released Thursday.

From 2007-2011 spending on the Supplemental Nutrition Assistance Program (the SNAP program, informally known as the food stamp program) increased 135 percent to reach a cost of $78 billion last year alone, the report reveals.

In the four year period CBO highlighted, the number of Americans on food stamps increased by 70 percent — “Nearly 45 million recipients, one out of every seven U.S. residents, received SNAP benefits in an average month in fiscal year 2011,” CBO explained.

CBO blamed three factors for the program’s expansion. They attribute 65 percent of the growth to a weak economy, 20 percent to temporarily higher benefit amounts resulting from Obama’s 2009 American Recovery and Reinvestment Act, and 15 percent on other factors such as food prices.

According to the agency, the program will continue to grow through 2014 before costs and participants beginning to decline. By 2022, the agency expects 34 million people each month will receive SNAP benefits, and the program will cost $73 billion.

A Republican Senate aide pointed out, however, that given the past trends a decline is rather unlikely.

“CBO always assumes the dollar amount will drop as the economy improves. That is not necessarily true,” a Republican aide told TheDC.

Indeed, while the recession officially ended in June 2009, the program has continued to expand.

“[W]ith his stimulus, President Obama significantly increased the size of the benefit. And despite the fact that the recession has been over for more than two years, that increased benefit won’t expire until the end of 2013. How is that justifiable when we have a $15 trillion national debt?” The aide added.

Alabama Republican Sen. Jeff Sessions has pointed to “categorical eligibility,” which permits states to make households automatically eligible for food stamps if they receive other federal benefits like Temporary Assistance for Needy Families (TANF) or counseling services, as a factor in the program’s expansion as well.

Last October, Sessions introduced legislation to end categorical eligibility. The CBO estimated it would have saved $10 billion over ten years without changing the standard eligibility requirements.

House Republicans are also eyeing food stamps as a way to reduce the deficit. They hope to trim $34 billion from the program over a decade.

The CBO offered policy options to help reduce the program’s burden, including changes “to the program’s eligibility rules that could alter the number of people participating in the program, Changes to the program’s rules that could modify benefit amounts, Changes to the administrative costs of the program, and Changes to the program’s funding, such as switching SNAP to a block grant.”

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