ement + Net Interest Payments as % of GDP 0% 1 1 T T T T T T 1980 1990 2000 2010E 2020E 2030E 2040E 2050E Source: Congressional Budget Office (CBO) Long-Term Budget Outlook (6/10). Note that entitlement spending includes federal government expenditures on Social Security, Medicare and Medicaid. Data in our chart is based