While the Americans with Disabilities Act (ADA) of 1990 requires public transit services, under specific conditions, to be accessible to persons with special needs, it did not impose a statutory deadline for fleet accessibility. The ADA did require all key stations to be accessible by July 1993, but allowed the Federal Transit Administration to grant an extension up to July 2020 for stations requiring structural modifications to bring them into compliance .
The ADA was enacted in 1990; data have been collected since 1993.
1. U.S. Department of Transportation, Federal Transit Administration, FY 2002 Performance Plan (Washington, DC: 2003), also available at http://www.fta.dot.gov/performfy2001/pg2.html, as of February 2003.