From the summary:
The Social Security Disability Insurance (DI) program pays cash benefits to nonelderly adults who have worked in the past but are judged to be unable to continue performing substantial work because of a disability. The program also pays benefits to some of those adults’ dependents. In 2015, the DI program paid a total of $143 billion, or about 0.8 percent of gross domestic product (GDP), in benefits to almost 9 million disabled beneficiaries and about 2 million of those beneficiaries’ spouses and children. Disabled beneficiaries generally are entitled to Medicare after a two-year waiting period; the cost of those benefits in 2015 was around $85 billion, or about 0.5 percent of GDP, CBO estimates.
How Have Enrollment and Spending Changed Since 1970?
Between 1970 and 2014, the share of working-age people who receive DI benefits as a result of their own disability and whose DI benefits are calculated on the basis of their own disability and work history more than tripled, increasing from 1.3 percent to 4.5 percent, before declining slightly in 2015. The increase in DI beneficiaries since 1970 is attributable to changes in the characteristics of the working-age population, in federal policy, and in employment…..