Daly et al., “The Future of Social Security Disability Insurance.”
 In 1994, with the DI program facing immediate insolvency, the Social Security Domestic Employment Reform Act of 1994 was signed into law. This act immediately increased the DI payroll tax rate from 0.6 percent to 0.94 percent through 1996, dropping to 0.85 percent for 1997–1999 and then rising to 0.9 percent beginning in 2000. Prior to the act, a reallocation from OASI to DI of 0.11 percentage point (from 0.6 to 0.71) beginning in 2000 had already been planned.
 Nonelderly people diagnosed with end-stage renal disease or amyotrophic lateral sclerosis automatically are not subject to the two-year waiting period for Medicare.
 Henry J. Kaiser Family Foundation, “Medicare Fact Sheet: Medicare and Nonelderly People with Disabilities,” Fact Sheet, September 2010, http://kaiserfamilyfoundation.files.wordpress.com/2013/01/8100.pdf (accessed June 2, 2014).
 Henry J. Kaiser Family Foundation, “Distribution of Medicare Beneficiaries by Eligibility Category,” http://kff.org/medicare/state-indicator/distribution-of-medicare-beneficiaries-by-eligibility-category-2/ (accessed June 2, 2014).
 Fletcher, “Disability Rolls Swell in a Rough Economy.”
 Su Liu and David Stapleton, “How Many SSDI Beneficiaries Leave the Rolls for Work? More Than You Might Think,” Center for Studying Disability Policy Disability Policy Research Brief No. 10-01, April 2010, http://www.mathematica-mpr.com/publications/PDFs/disability/ssdi_benef_ib.pdf (accessed June 2, 2014).