source: November 19th Economist
The magazine explains:
Most of the growth in the deficit comes from spending, which averaged 21% of GDP from 1980 to 2007 but will approach 25% by 2019, according to the CBO (see chart 1). Some of that comes from interest charges on the debt, expected to more than triple from their current 5% of total spending. But entitlements are the elephant in the budget. On current policies, pensions and health care for the retired (Social Security and Medicare, respectively) and health care for the poor (Medicaid) will grow from 10% of GDP in 2011 to 18% by 2050.Agreed.