In 2016, Social Security income from payroll contributions, tax revenues, and interest on reserves exceeded outgo by $35 billion, leaving a surplus. Reserves, now at $2.8 trillion, are projected to grow to $3.0 trillion by the end of 2021. If Congress takes no action before then, reserves would be drawn down to pay benefits. The Disability Insurance (DI) Trust Fund is projected to cover scheduled benefits until 2028, and the Old-Age and Survivors (OASI) Trust Fund until 2035. On a combined OASDI basis, Social Security is fully funded until 2034, but faces a projected shortfall thereafter. After the projected depletion of the combined OASDI trust funds, Social Security contributions and tax revenues would continue to be received and would cover about 77 percent of scheduled benefits (and administrative costs, which are less than 1 percent of outgo). The long-range actuarial shortfall over 75 years is projected to be 2.83 percent of taxable payroll – that is, 2.83 percent of all earnings that are subject to Social Security contributions. This projected long-term revenue shortfall increased from 2.66 percent of taxable payroll, which was reported in the 2016 Trustees Report. Timely revenue increases and/or benefit reductions could bring the program into long-term balance, preventing the projected shortfall.