In which year was Memorial Day moved from may 30th to the fourth monday in may?

Memorial Day was not declared the official name by Federal law until 1967. On June 28, 1968, the United States Congress passed the Uniform Holidays Bill, which moved three holidays from their traditional dates to a specified Monday in order to create a convenient three-day weekend. The holidays included Washington's Birthday, now celebrated as Presidents' Day; Veterans Day, and Memorial Day. The change moved Memorial Day from its traditional May 30 date to the last Monday in May. The law took effect at the federal level in 1971