Amendments to the Voting Rights Act of 1965
The U.S. Congress enacted major amendments to the Voting Rights Act of 1965 in 1970, 1975, 1982, 1992, and 2006. Each of these amendments coincided with an impending expiration of some of the Act's special provisions, which originally were set to expire by 1970.
Source: Wikipedia — Amendments to the Voting Rights Act of 1965 (CC BY-SA 4.0)