Federal debt held by the public now exceeds 70 percent of the nation's annual output (gross domestic product, or GDP) and stands at a higher percentage than in any year since 1950. Under an assumption whereby current laws generally remain unchanged, federal debt will be 77 per-cent of GDP in 2023, the Congressional Budget Office (CBO) projects.1 Such a large amount of federal debt will reduce the nation's output and income below what would occur if the debt was smaller, and it raises the risk of a fis-cal crisis (in which the government would lose the ability to borrow money at affordable interest rates). Moreover, the aging of the population and rising health care costs will tend to push debt even higher in the following decades. In addition, those projections of debt under current law incorporate scheduled changes in policies that will serve to restrain the growth of debt. For example, under cur-rent law, some significant tax provisions will expire at the end of this year or in later years, increasing revenues; automatic spending cuts included in the Budget Control Act of 2011 and modified in the American Taxpayer Relief Act of 2012 will go into effect on March 1, 2013; and Medicare's payment rates for physicians' services will fall in January 2014. If future legislation prevented those changes from taking effect and did not make other policy changes with offsetting budgetary effects, federal debt would be considerably higher than the amount projected under current law.