| Year | Value | | 2022 | 15,446,047 | | 2021 | 15,196,430 | | 2020 | 14,935,196 | | 2019 | 14,670,338 | | 2018 | 14,405,827 | | 2017 | 14,134,437 | | 2016 | 13,852,529 | | 2015 | 13,564,948 | | 2014 | 13,275,977 | | 2013 | 12,989,920 | | 2012 | 12,704,037 | | 2011 | 12,419,447 | | 2010 | 12,146,783 | | 2009 | 11,881,653 | | 2008 | 11,621,238 | | 2007 | 11,363,537 | | 2006 | 11,118,137 | | 2005 | 10,887,626 | | 2004 | 10,654,996 | | 2003 | 10,424,994 | | 2002 | 10,199,547 | | 2001 | 9,978,658 | | 2000 | 9,762,505 | | 1999 | 9,553,704 | | 1998 | 9,351,767 | | 1997 | 9,167,398 | | 1996 | 8,984,800 | | 1995 | 8,786,711 | | 1994 | 8,591,695 | | 1993 | 8,404,113 | | 1992 | 8,223,082 | | 1991 | 8,047,399 | | 1990 | 7,869,863 | | 1989 | 7,688,773 | | 1988 | 7,510,059 | | 1987 | 7,332,373 | | 1986 | 7,154,599 | | 1985 | 6,995,032 | | 1984 | 6,856,646 | | 1983 | 6,718,117 | | 1982 | 6,582,972 | | 1981 | 6,452,105 | | 1980 | 6,322,519 | | 1979 | 6,195,229 | | 1978 | 6,073,395 | | 1977 | 5,957,720 | | 1976 | 5,851,697 | | 1975 | 5,748,837 | | 1974 | 5,643,692 | | 1973 | 5,547,370 | | 1972 | 5,458,127 | | 1971 | 5,373,259 | | 1970 | 5,289,220 | | 1969 | 5,205,100 | | 1968 | 5,122,818 | | 1967 | 5,042,174 | | 1966 | 4,964,771 | | 1965 | 4,889,820 | | 1964 | 4,817,483 | | 1963 | 4,749,087 | | 1962 | 4,683,541 | | 1961 | 4,620,091 | | 1960 | 4,558,446 |
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