CBO’s Long-Term Social Security Projections: Changes Since 2017 and Comparisons With the Social Security Trustees’ Projections – December 3, 2018: “This report explains the changes to CBO’s long-term Social Security projections since last year and compares CBO’s projections with those of the Social Security Trustees.

• The projected 75-year actuarial balance, a commonly used measure of the system’s financial condition, has not changed as a percentage of gross domestic product (GDP) since last year, remaining at −1.5 percent of GDP (that is, a deficit of 1.5 percent). As a percentage of taxable payroll, the projected 75-year actuarial balance has improved slightly from −4.5 percent to −4.4 percent.
• Changes to projections of three key inputs have improved the Social Security system’s projected finances: the share of earnings that is subject to Social Security payroll taxes, the labor force participation rate, and interest rates.
• Those improvements have been partially offset by including an additional year of deficit, 2092, in the calculation of the actuarial balance. Technical changes also collectively worsen the 75-year outlook…”