NEW: State History of the Minimum Legal Drinking Age, 1933-present – Following the passage of the 26th Amendment on July 1, 1971, which lowered the legal voting age from 21 to 18, 30 US states lowered their minimum legal drinking age (MLDA) for alcohol from 21 to 18, 19, or 20. In 1984, the enactment of the National Minimum Drinking Age Act of 1984 prompted states to raise their legal age for purchase or public possession of alcohol to 21 or risk losing millions in federal highway funds. By 1988, all 50 states had raised their MLDA to 21. California (1933) and Oregon (1933) have the nation’s oldest MLDA 21 laws while South Dakota (Apr. 1, 1988) and Wyoming (July 1, 1988) have the most recent MLDA 21 laws.