Visitor Stats

Newsroom of the Smithsonian
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Because the Smithsonian museums are free, we cannot base our visit tallies on a number of tickets sold.

Smithsonian security officers use hand clickers to count everyone entering the museums (in some buildings they count people leaving) through public entrances during the hours the museums are open. The counts sometimes include staff, as well as visitors who leave the museum and return. A person visiting three Smithsonian museums on any given day will be counted three times. For these reasons, we always refer to the numbers below as "visits" rather than "visitors." The newest Smithsonian museum, the National Museum of African American History and Culture (NMAAHC), has an automated counting system that counts visitors (and staff) as they enter the museum.

Visit numbers are compiled on a calendar-year basis. Since 2001, the total visits to the Smithsonian have also reflected the number of visits to the National Zoo.

Numbers are rounded to the nearest thousand or tenth of a million (M), depending on volume.

Totals for 2023 

Smithsonian American Art Museum (With the Renwick Gallery) 1.4 M
National Portrait Gallery 1.1 M
National Museum of African American History and Culture 1.6 M
National Museum of African Art 130,569
National Air and Space Museum 1.9 M
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.2 M
National Museum of American History 2.1 M
National Museum of the American Indian (Washington, D.C.) 704,074
National Museum of the American Indian Heye Center (New York City) 329,231
Anacostia Community Museum 15,516
Arts and Industries Building 31,180
Cooper Hewitt, Smithsonian Design Museum 152,591
Hirshhorn Museum and Sculpture Garden 714,684
National Museum of Natural History 4.4 M
Renwick Gallery of the Smithsonian American Art Museum 281,035
Smithsonian Institution Building, "The Castle" 58,623
Arthur M. Sackler Gallery  189,819
Freer Gallery of Art  333,598
National Postal Museum 170,013
National Zoo 1.9 M
Total Visits in 2023 17.7 M

Due to the COVID-19 pandemic, most Smithsonian museums were open five days a week. Starting in March 2022, museums gradually returned to traditional schedules.

Totals for 2022 

Smithsonian American Art Museum (With the Renwick Gallery) 1.1 M
National Portrait Gallery 953,653
National Museum of African American History and Culture 1.2M
National Museum of African Art 90,968
National Air and Space Museum 418,864
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.1 M
National Museum of American History 1.8 M
National Museum of the American Indian (Washington, D.C.) 552,928
National Museum of the American Indian Heye Center (New York City) 239,435
Anacostia Community Museum 7,922
Arts and Industries Building 410,250
Cooper Hewitt, Smithsonian Design Museum 118,003
Hirshhorn Museum and Sculpture Garden 828,949
National Museum of Natural History 3.9 M
Renwick Gallery of the Smithsonian American Art Museum 195,592
Smithsonian Institution Building, "The Castle" 875,417
Arthur M. Sackler Gallery  127,594
Freer Gallery of Art  238,519
National Postal Museum 120,818
National Zoo 1.5 M
Total Visits in 2022 (as of July) 14.9 M

All Smithsonian museums and the National Zoo closed to the public on March 14, 2020 due to COVID-19. The museums and the National Zoo reopened in phases starting in May 2021 with timed tickets and a limited schedule. 

Totals for 2021

Smithsonian American Art Museum (With the Renwick Gallery) 420,491
National Portrait Gallery 329,683
National Museum of African American History and Culture 392,996
National Museum of African Art 31,877
National Air and Space Museum 410,658
National Air and Space Museum's Steven F. Udvar-Hazy Center 561,577
National Museum of American History 570,218
National Museum of the American Indian (Washington, D.C.) 206,895
National Museum of the American Indian Heye Center (New York City) 56,568
Anacostia Community Museum 1,885
Arts and Industries Building 85,520
Cooper Hewitt, Smithsonian Design Museum 62,214
Hirshhorn Museum and Sculpture Garden 167,155
National Museum of Natural History 982,080
Renwick Gallery of the Smithsonian American Art Museum 90,808
Smithsonian Institution Building, "The Castle" 225,107
Arthur M. Sackler Gallery  13,217
Freer Gallery of Art  81,605
National Postal Museum 21,627
National Zoo 957,466
Total Visits in 2021 5.2 M

All Smithsonian museums and the National Zoo closed to the public on March 14, 2020 due to COVID-19. Seven museums and the National Zoo reopened in phases between July and Sept. with timed tickets and a limited schedule. The museums and the National Zoo closed again on Nov. 23.

Totals for 2020

Smithsonian American Art Museum (With the Renwick Gallery) 387,403
National Portrait Gallery 321,286
National Museum of African American History and Culture 367,727
National Museum of African Art 23,111
National Air and Space Museum 267,003
National Air and Space Museum's Steven F. Udvar-Hazy Center 311,548
National Museum of American History 310,645
National Museum of the American Indian (Washington, D.C.) 143,532
National Museum of the American Indian Heye Center (New York City) 49,646
Anacostia Community Museum 6,137
Arts and Industries Building 0
Cooper Hewitt, Smithsonian Design Museum 38,582
Hirshhorn Museum and Sculpture Garden 133,050
National Museum of Natural History 572,638
Renwick Gallery of the Smithsonian American Art Museum 66,117
S. Dillon Ripley Center 27,188
Smithsonian Institution Building, "The Castle" 100,002
Arthur M. Sackler Gallery  30,051
Freer Gallery of Art  49,280
National Postal Museum 84,862
National Zoo 356,463
Total Visits in 2020 3.3 M

Totals for 2019 

Smithsonian American Art Museum (With the Renwick Gallery) 2M
National Portrait Gallery 1.7M
National Museum of African American History and Culture 2M
National Museum of African Art 129,572
National Air and Space Museum 3.2M
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.3M
National Museum of American History 2.8M
National Museum of the American Indian (Washington, D.C.) 960,933
National Museum of the American Indian Heye Center (New York City) 348,599
Anacostia Community Museum 8,034
Arts and Industries Building 25,967
Cooper Hewitt, Smithsonian Design Museum 263,637
Hirshhorn Museum and Sculpture Garden 891,114
National Museum of Natural History 4.2M
Renwick Gallery of the Smithsonian American Art Museum 314,068
S. Dillon Ripley Center 144,169
Smithsonian Institution Building, "The Castle" 965,512
Arthur M. Sackler Gallery  148,242
Freer Gallery of Art  298,094
National Postal Museum 501,204
National Zoo 1.8M
Total Visits in 2019 22.1M

Totals for 2018 

Smithsonian American Art Museum (With the Renwick Gallery) 3.15M
National Portrait Gallery 2.3M
National Museum of African American History and Culture 1.9M
National Museum of African Art 141,890
National Air and Space Museum 6.2M
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.5M
National Museum of American History 4.1M
National Museum of the American Indian (Washington, D.C.) 1.1M
National Museum of the American Indian Heye Center (New York City) 405,989
Anacostia Community Museum 33,709
Arts and Industries Building 19,341
Cooper Hewitt, Smithsonian Design Museum 316,957
Hirshhorn Museum and Sculpture Garden 881,553
National Museum of Natural History 4.8M
Renwick Gallery of the Smithsonian American Art Museum 849,515
S. Dillon Ripley Center 133,767
Smithsonian Institution Building, "The Castle" 1M
Arthur M. Sackler Gallery  133,503
Freer Gallery of Art  282,755
National Postal Museum 495,961
National Zoo 1.8M
Total Visits in 2018 28.5M
Donald W. Reynolds Center for American Art and Portraiture
(Smithsonian American Art Museum and The National Portrait Gallery)
1.3M
National Museum of African American History and Culture 2.4M
National Museum of African Art 159,000
National Air and Space Museum 7M
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.6M
National Museum of American History 3.8M
National Museum of the American Indian (Washington, D.C.) 1.2M
National Museum of the American Indian Heye Center (New York City) 437,000
Anacostia Community Museum 37,000
Arts and Industries Building 59,000
Cooper Hewitt, Smithsonian Design Museum 338,000
Hirshhorn Museum and Sculpture Garden 1.1M
National Museum of Natural History 6M
Renwick Gallery of the Smithsonian American Art Museum 414,000
S. Dillon Ripley Center 161,000
Smithsonian Institution Building, "The Castle" 1.1M
Arthur M. Sackler Gallery  178,000
Freer Gallery of Art  75,000
National Postal Museum 486,000
National Zoo 2M
Total Visits in 2017 30M
Donald W. Reynolds Center for American Art and Portraiture
(Smithsonian American Art Museum and The National Portrait Gallery)
1.2M
National Museum of African American History and Culture 733,000
National Museum of African Art 206,000
National Air and Space Museum 7.5M
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.6M
National Museum of American History 3.8M
National Museum of the American Indian (Washington, D.C.) 1.1M
National Museum of the American Indian Heye Center (New York City) 474,000
Anacostia Community Museum 28,000
Arts and Industries Building 64,000
Cooper Hewitt, Smithsonian Design Museum 418,000
Hirshhorn Museum and Sculpture Garden 659,000
National Museum of Natural History 7.1M
Renwick Gallery of the Smithsonian American Art Museum 764,000
S. Dillon Ripley Center 166,000
Smithsonian Institution Building, "The Castle" 1.1M
Arthur M. Sackler Gallery 213,000
Freer Gallery of Art 10,000
National Postal Museum 398,000
National Zoo 2.7M
Total Visits in 2016 30.2M
Donald W. Reynolds Center for American Art and Portraiture
(Smithsonian American Art Museum and The National Portrait Gallery)
1.3M
National Museum of African Art 213,000
National Air and Space Museum 6.9M
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.6M
National Museum of American History 4.1M
National Museum of the American Indian (Washington, D.C.) 1.2M
National Museum of the American Indian Heye Center (New York City) 486,000
Anacostia Community Museum 30,000
Arts and Industries Building Closed for renovation
Cooper-Hewitt, National Museum of Design (New York City) 265,000
Hirshhorn Museum and Sculpture Garden 681,000
National Museum of Natural History 6.9M
Renwick Gallery of the Smithsonian American Art Museum 164,000
S. Dillon Ripley Center 145,000
Smithsonian Institution Building, "The Castle" 1.1M
Arthur M. Sackler Gallery 150,000
Freer Gallery of Art 389,000
National Postal Museum 357,000
National Zoo 2.2M
Total Visits in 2015 28.2M
Donald W. Reynolds Center for American Art and Portraiture
(Smithsonian American Art Museum and The National Portrait Gallery)
1.1m
National Museum of African Art 203k
National Air and Space Museum 6.7m
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.3m
National Museum of American History 4m
National Museum of the American Indian (Washington, D.C.) 1.3m
National Museum of the American Indian Heye Center (New York City) 584kk
Anacostia Community Museum 42k
Arts and Industries Building Closed for renovation
Cooper-Hewitt, National Museum of Design (New York City) 27k
Hirshhorn Museum and Sculpture Garden 552k
National Museum of Natural History 7.3m
Renwick Gallery of the Smithsonian American Art Museum Closed for renovation
S. Dillon Ripley Center 146k
Smithsonian Institution Building, "The Castle" 1.2m
Arthur M. Sackler Gallery 182k
Freer Gallery of Art 371k
National Postal Museum 401k
National Zoo 2.5m
Total Visits in 2014 28m
Donald W. Reynolds Center for American Art and Portraiture
(Smithsonian American Art Museum and The National Portrait Gallery)
1.1M
National Museum of African Art 216k
National Air and Space Museum 7.0M
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.3M
National Museum of American History 4.9M
National Museum of the American Indian (Washington, D.C.) 1.4M
National Museum of the American Indian Heye Center (New York City) 595k
Anacostia Community Museum 38k
Arts and Industries Building Closed for renovation
Cooper-Hewitt, National Museum of Design (New York City) Closed for renovation
Hirshhorn Museum and Sculpture Garden 645k
National Museum of Natural History 8.0M
Renwick Gallery of the Smithsonian American Art Museum 122k
S. Dillon Ripley Center 198k
Smithsonian Institution Building, "The Castle" 1.3M
Arthur M. Sackler Gallery 217k
Freer Gallery of Art 396k
National Postal Museum 288k
National Zoo 2.0M
Total Visits in 2013 30.0M
Donald W. Reynolds Center for American Art and Portraiture
(Smithsonian American Art Museum and The National Portrait Gallery)
1M
National Museum of African Art 353,959
National Air and Space Museum 6.8M
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.4M
National Museum of American History 4.8M
National Museum of the American Indian (Washington, D.C.) 1.6M
National Museum of the American Indian Heye Center (New York City) 441,397
Anacostia Community Museum 31,168
Arts and Industries Building Closed for renovation
Cooper-Hewitt, National Museum of Design (New York City) Closed for renovation
Hirshhorn Museum and Sculpture Garden 753,258
National Museum of Natural History 7.6M
Renwick Gallery of the Smithsonian American Art Museum 162,051
S. Dillon Ripley Center 465,654
Smithsonian Institution Building, "The Castle" 1.4M
Arthur M. Sackler Gallery 359,813
Freer Gallery of Art 509,930
National Postal Museum 321,953
National Zoo 2.3M
Total Visits in 2012 30.3M
Donald W. Reynolds Center for American Art and Portraiture
(Smithsonian American Art Museum and The National Portrait Gallery)
948,345
National Museum of African Art 384,693
National Air and Space Museum 7 million
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.2 million
National Museum of American History 4.6 million
National Museum of the American Indian (Washington, D.C.) 1.4 million
National Museum of the American Indian Heye Center (New York City) 365,512
Anacostia Community Museum 48,230
Arts and Industries Building Closed for renovation
Cooper-Hewitt, National Museum of Design (New York City) (Closed for renovation 7/2011) 190,752
Hirshhorn Museum and Sculpture Garden 623,039
National Museum of Natural History 6.6 million
Renwick Gallery of the Smithsonian American Art Museum 164,925
S. Dillon Ripley Center 464,315
Smithsonian Institution Building, "The Castle" 1.5 million
Arthur M. Sackler Gallery 387,694
Freer Gallery of Art 557,983
National Postal Museum 325,900
National Zoo 1.9 million
Total Visits in 2011 28.6 million
Anacostia Community Museum 58,000
Arts and Industries Building Closed for renovation
Cooper-Hewitt, National Museum of Design (New York City) 181,000
Donald W. Reynolds Center for American Art and Portraiture
(Smithsonian American Art Museum and The National Portrait Gallery)
1.1 million
Freer Gallery of Art 488,000
Hirshhorn Museum and Sculpture Garden 621,000
National Air and Space Museum 8.3 million
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.1 million
National Museum of African Art 310,000
National Museum of American History 4.2 million
National Museum of the American Indian (Washington, D.C.) 1.3 million
National Museum of the American Indian Heye Center (New York City) 300,000
National Museum of Natural History 6.8 million
National Zoo 2.3 million
National Postal Museum 343,000
Renwick Gallery of the Smithsonian American Art Museum 151,000
Arthur M. Sackler Gallery 308,000
S. Dillon Ripley Center 363,000
Smithsonian Institution Building, "The Castle" 1.8 million
Total Visits in 2010 30.2 million
Anacostia Community Museum 34,000
Arts and Industries Building Closed for renovation
Cooper-Hewitt, National Museum of Design (New York City) 172,000
Donald W. Reynolds Center for American Art and Portraiture
(Smithsonian American Art Museum and The National Portrait Gallery)
1 million
Freer Gallery of Art 634,000
Hirshhorn Museum and Sculpture Garden 668,000
National Air and Space Museum 7 million
National Air and Space Museum's Steven F. Udvar-Hazy Center 440,000
National Museum of African Art 403,000
National Museum of American History 4.4 million
National Museum of the American Indian (Washington, D.C.) 1.4 million
National Museum of the American Indian Heye Center (New York City) 286,000
National Museum of Natural History 7.4 million
National Zoo 2.2 million
National Postal Museum 349,000
Renwick Gallery of the Smithsonian American Art Museum 161,000
Arthur M. Sackler Gallery 349,000
S. Dillon Ripley Center 439,000
Smithsonian Institution Building, "The Castle" 1.9 million
Total Visits in 2009 30 million
Anacostia Community Museum 36,000
Arts and Industries Building Closed for renovation
Cooper-Hewitt, National Museum of Design (New York City) 154,000
Donald W. Reynolds Center for American Art and Portraiture
(Smithsonian American Art Museum and The National Portrait Gallery)
1 million
Freer Gallery of Art 603,000
Hirshhorn Museum and Sculpture Garden 670,000
National Air and Space Museum 7 million
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.2 million
National Museum of African Art 322,000
National Museum of American History 480,000 (reopened Nov. 21 after a 2-year renovation)
National Museum of the American Indian (Washington, D.C.) 1.5 million
National Museum of the American Indian Heye Center (New York City) 306,000
National Museum of Natural History 7 million
National Zoo 2.1 million
National Postal Museum 334,000
Renwick Gallery of the Smithsonian American Art Museum 137,000
Arthur M. Sackler Gallery 288,000
S. Dillon Ripley Center 453,000
Smithsonian Institution Building, "The Castle" 1.7 million
Total Visits in 2008 25.2 million
Anacostia Community Museum 37,000
Arts and Industries Building Closed for renovation
Cooper-Hewitt, National Museum of Design (New York City) 224,000
Donald W. Reynolds Center for American Art and Portraiture
(Smithsonian American Art Museum and The National Portrait Gallery)
786,000
Freer Gallery of Art 590,000
Hirshhorn Museum and Sculpture Garden 740,000
National Air and Space Museum 6 million
National Air and Space Museum's Steven F. Udvar-Hazy Center 1 million
National Museum of African Art 310,000
National Museum of American History Closed for renovation
National Museum of the American Indian (Washington, D.C.) 1.8 million
National Museum of the American Indian Heye Center (New York City) 281,000
National Museum of Natural History 7.1 million
National Zoo 2.6 million
National Postal Museum 326,000
Renwick Gallery of the Smithsonian American Art Museum 132,000
Arthur M. Sackler Gallery 308,000
S. Dillon Ripley Center 296,000
Smithsonian Institution Building, "The Castle" 1.6 million
Total Visits in 2007 24.2 million
Anacostia Community Museum 46,000
Arts and Industries Building Closed for renovation
Cooper-Hewitt, National Museum of Design (New York City) 207,000
Donald W. Reynolds Center for American Art and Portraiture
(Smithsonian American Art Museum and The National Portrait Gallery)
480,000
(for last 6 months only)
Freer Gallery of Art 462,000
Hirshhorn Museum and Sculpture Garden 757,000
National Air and Space Museum 5 million
National Air and Space Museum's Steven F. Udvar-Hazy Center 1 million
National Museum of African Art 211,000
National Museum of American History 2.4 million
Closed for renovation
National Museum of the American Indian (Washington, D.C.) 1.6 million
National Museum of the American Indian Heye Center (New York City) 240,000
National Museum of Natural History 5.8 million
National Zoo 2.6 million
National Postal Museum 390,000
Renwick Gallery of the Smithsonian American Art Museum 155,000
Arthur M. Sackler Gallery 260,000
S. Dillon Ripley Center 241,000
Smithsonian Institution Building, "The Castle" 1.3 million
Total Visits in 2006 23.2 million

2005

Totals for 2005
Anacostia Community Museum 25,000
Arts and Industries Building Closed for renovation
Cooper-Hewitt, National Museum of Design (New York City) 129,000
Freer Gallery of Art 323,000
Hirshhorn Museum and Sculpture Garden 699,000
National Air and Space Museum 6.1 million
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.2 million
National Museum of African Art 158,000
National Museum of American History 3.0 million
National Museum of the American Indian (Washington, D.C.) 2.2 million
National Museum of the American Indian Heye Center (New York City) 299,000
National Museum of Natural History 5.6 million
National Portrait Gallery and Smithsonian American Art Closed for renovation
National Zoo 1.8 million
National Postal Museum 519,000
Renwick Gallery of the Smithsonian American Art Museum 143,000
Arthur M. Sackler Gallery 147,000
S. Dillon Ripley Center 198,000
Smithsonian Institution Building, "The Castle" 1.3 million
Total Visits in 2005 24 million

2004

Totals for 2004
Anacostia Community Museum 22,000
Arts and Industries Building Closed for renovation
Cooper-Hewitt, National Museum of Design (New York City) 150,000
Freer Gallery of Art 355,000
Hirshhorn Museum and Sculpture Garden 659,000
National Air and Space Museum 4.9 million
National Air and Space Museum's Steven F. Udvar-Hazy Center 1.6 million
National Museum of African Art 165,000
National Museum of American History 2.9 million
National Museum of the American Indian (Washington, D.C.) 820,000
National Museum of the American Indian Heye Center (New York City) 254,000
National Museum of Natural History 4.4 million
National Portrait Gallery and Smithsonian American Art Closed for renovation
National Zoo 1.8 million
National Postal Museum 353,000
Renwick Gallery of the Smithsonian American Art Museum 115,000
Arthur M. Sackler Gallery 188,000
S. Dillon Ripley Center 178,000
Smithsonian Institution Building, "The Castle" 1.5 million
Total Visits in 2004 20.4 million

2003

Totals for 2003
Anacostia Community Museum 29,000
Arts and Industries Building 886,000
Cooper-Hewitt, National Museum of Design (New York City) 149,000
Freer Gallery of Art 315,000
Hirshhorn Museum and Sculpture Garden 660,000
National Air and Space Museum 9.4 million
National Air and Space Museum's Steven F. Udvar-Hazy Center 220,000
National Museum of African Art 170,000
National Museum of American History 2.6 million
National Museum of the American Indian Heye Center (New York City) 266,000
National Museum of Natural History 5.2 million
National Portrait Gallery and Smithsonian American Art Closed for renovation
National Zoo 1.8 million
National Postal Museum 313,000
Renwick Gallery of the Smithsonian American Art Museum 168,000
Arthur M. Sackler Gallery 162,000
S. Dillon Ripley Center 239,000
Smithsonian Institution Building, "The Castle" 1.1 million
Total Visits in 2003 24 million

2002

Totals for 2002
Anacostia Community Museum 31,000
Arts and Industries Building 900,000
Cooper-Hewitt, National Museum of Design (New York City) 136,000
Freer Gallery of Art 405,000
Hirshhorn Museum and Sculpture Garden 691,000
National Air and Space Museum 8,500,000
National Museum of African Art 179,000
National Museum of American History 4,200,000
National Museum of the American Indian Heye Center (New York City) 340,000
National Museum of Natural History 6,260,000
National Portrait Gallery and Smithsonian American Art Closed for renovation
National Postal Museum 321,000
Renwick Gallery of the Smithsonian American Art Museum 150,000
Arthur M. Sackler Gallery 214,000
S. Dillon Ripley Center 280,000
Smithsonian Institution Building, "The Castle" 1,600,000
Total Visits in 2002 26.3 million

2001

Totals for 2001
Anacostia Community Museum Closed for renovation
Arts and Industries Building 1.2 million
Cooper-Hewitt, National Museum of Design (New York City) 138,000
Freer Gallery of Art 295,000
Hirshhorn Museum and Sculpture Garden 718,000
National Air and Space Museum 9.3 million
National Museum of African Art 208,000
National Museum of American History 5.2 million
National Museum of the American Indian Heye Center (New York City) 361,000
National Museum of Natural History 8.4 million
National Portrait Gallery and Smithsonian American Art Closed for renovation
National Postal Museum 377,000
Renwick Gallery of the Smithsonian American Art Museum 141,000
Arthur M. Sackler Gallery 188,000
S. Dillon Ripley Center 489,000
Smithsonian Institution Building, "The Castle" 1.8 million
Total Visits in 2001 31.7 million
Total Visits, 1970-2000
2000 31.1 million
1999 28.5 million
1998 28.6 million
1997 27.4 million
1996 22.4 million
1995 23.6 million
1994 24.7 million
1993 25.9 million
1992 26.6 million
1991 25 million
1990 25 million
1989 24 million
1988 28 million
1987 27 million
1986 22.7 million
1985 23.7 million
1984 30.1 million
1983 25.8 million
1982 22.6 million
1981 22.1 million
1980 21.1 million
1979 23.1 million
1978 24.7 milllion
1977 22.9 million
1976 20.4 million
1975 17.8 million
1974 14.3 million
1973 15 million
1972 15 million
1971 14.3 million
1970 13.4