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1855: 42 visitors
1907: 7,000
1912: 11,000
1916: 28,000
1922: 100,000
1927: 500,000
1941: 600,000
1943: 128,000 (World War II)
1954: 1,100,000
1984: 2,842,942
1995: 4,101,928
*All figures except 1984 and 1995 are estimates
Source: National Park Service.
