We estimate that the HI trust fund's balance is exhausted in 2040. The balance generally increases through 2031, but spending begins to outstrip income in the following year.

Social Security is the largest single program in the federal budget. In fiscal year 2018, outlays for Social Security benefits totaled $977 billion, or almost one-quarter of federal spending. The benefits are paid from two designated Social Security trust funds. On the basis of the analysis described in The 2018 Long-Term Budget Outlook, which incorporates the assumption that current law generally does not change, the Congressional Budget Office projects that those trust funds combined would be exhausted in calendar year 2031, requiring the amounts scheduled to be paid in 2032 to be reduced by 26 percent.