the beginning of medicare
1 In 1965, the budget for Medicare was around $10 billion and 19 million individuals signed up for Medicare during its first year. 2  In 1966, Medicareâs coverage took effect, as Americans age 65 and older were enrolled in Part A and millions of other seniors signed up for Part B. In 1965, the budget for Medicare was around $10 billion and 19 million individuals signed up for Medicare during its first year. 2  In 1966, Medicareâs coverage took effect, as Americans age 65 and older were enrolled in Part A and millions of other seniors signed up for Part B.