My column today looks at how the social safety net has changed over time. Most of the numbers are based on research by Robert A. Moffitt, an economics professor at Johns Hopkins University who has studied the social safety net in the years before, during and after the Great Recession.

Moffitt finds that spending on the major federal social safety net programs has grown over time, even after you adjust for inflation and population growth.

Source: Robert A. Moffitt.

Between 1970 and 2010, per-capita spending on the federal social safety net nearly quadrupled. Most of the growth, in raw dollar terms, came from “social insurance” programs. These include Old-Age and Survivors Insurance (commonly referred to as “Social Security”), Medicare, unemployment insurance, workers’ compensation and disability insurance. Means-tested benefits — that is, benefits that are based on recipients’ income and are intended to target the poor — have grown less in dollar terms, especially once you strip out Medicaid.

Here’s how spending per capita has changed on some of the larger means-tested programs:

Source: Robert A. Moffitt. AFDC/TANF=Aid to Families with Dependent Children/Temporary Assistance for Needy Families; EITC=Earned Income Tax Credit; SSI=Supplemental Security Income; SNAP=Supplemental Nutrition Assistance Program.

As you can see, traditional welfare payments — formerly known as Aid to Families with Dependent Children (A.F.D.C.) and now Temporary Assistance for Needy Families  (T.A.N.F.) has fallen dramatically. Meanwhile spending on the Earned Income Tax Credit (E.I.T.C.) has grown. Spending on food stamps (also known as S.N.A.P., or Supplemental Nutrition Assistance Program) has climbed quite a lot too, thanks to a combination of relaxed eligibility requirements, greater outreach to families that might not have known they qualified and increased need during a period of high unemployment.

Finally, here are the changes in social insurance spending. You’ll notice a big jump in the recent years in spending on most of these programs, driven partly by the aging of baby boomers and partly by the downturn.

Source: Robert A. Moffitt. OASI=Old-Age and Survivors Insurance; UI=Unemployment Insurance; DI=Disability Insurance.

One further observation. Spending on many of these programs — like unemployment insurance and food stamps — will likely decrease or decelerate as the economy recovers, and people gain jobs and cease to be eligible for various kinds of public assistance. But that’s not true for all programs. For example, once they’re on the disability or Social Security rolls, people usually continue receiving these benefits for the rest of their lives.