| Year | Value | | 2022 | 23,848,253 | | 2021 | 23,153,140 | | 2020 | 22,431,520 | | 2019 | 21,707,475 | | 2018 | 20,994,287 | | 2017 | 20,303,726 | | 2016 | 19,617,063 | | 2015 | 18,983,798 | | 2014 | 18,416,102 | | 2013 | 17,886,355 | | 2012 | 17,387,117 | | 2011 | 16,899,880 | | 2010 | 16,424,860 | | 2009 | 15,962,058 | | 2008 | 15,512,657 | | 2007 | 15,074,658 | | 2006 | 14,647,855 | | 2005 | 14,236,112 | | 2004 | 13,837,865 | | 2003 | 13,443,274 | | 2002 | 13,037,567 | | 2001 | 12,644,368 | | 2000 | 12,269,915 | | 1999 | 11,895,320 | | 1998 | 11,520,334 | | 1997 | 11,186,019 | | 1996 | 10,868,349 | | 1995 | 10,579,985 | | 1994 | 10,298,404 | | 1993 | 9,963,983 | | 1992 | 9,629,879 | | 1991 | 9,310,255 | | 1990 | 9,012,225 | | 1989 | 8,726,862 | | 1988 | 8,450,090 | | 1987 | 8,185,083 | | 1986 | 7,930,993 | | 1985 | 7,693,783 | | 1984 | 7,468,747 | | 1983 | 7,258,319 | | 1982 | 7,067,708 | | 1981 | 6,894,402 | | 1980 | 6,740,630 | | 1979 | 6,592,289 | | 1978 | 6,427,548 | | 1977 | 6,252,307 | | 1976 | 6,082,650 | | 1975 | 5,918,011 | | 1974 | 5,758,688 | | 1973 | 5,609,314 | | 1972 | 5,470,966 | | 1971 | 5,327,511 | | 1970 | 5,170,682 | | 1969 | 5,009,712 | | 1968 | 4,849,199 | | 1967 | 4,692,441 | | 1966 | 4,542,813 | | 1965 | 4,399,721 | | 1964 | 4,262,563 | | 1963 | 4,130,869 | | 1962 | 4,004,929 | | 1961 | 3,884,829 | | 1960 | 3,769,494 |
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