| Year | Value | | 2022 | 18,537,999 | | 2021 | 18,221,219 | | 2020 | 17,856,205 | | 2019 | 17,416,409 | | 2018 | 16,903,279 | | 2017 | 16,394,798 | | 2016 | 15,909,951 | | 2015 | 15,433,619 | | 2014 | 14,920,856 | | 2013 | 14,367,866 | | 2012 | 13,829,553 | | 2011 | 13,337,295 | | 2010 | 12,881,980 | | 2009 | 12,459,146 | | 2008 | 12,076,631 | | 2007 | 11,713,582 | | 2006 | 11,356,514 | | 2005 | 11,012,967 | | 2004 | 10,676,491 | | 2003 | 10,342,496 | | 2002 | 10,030,326 | | 2001 | 9,708,455 | | 2000 | 9,361,692 | | 1999 | 9,026,505 | | 1998 | 8,702,282 | | 1997 | 8,396,269 | | 1996 | 8,133,248 | | 1995 | 7,893,346 | | 1994 | 7,655,422 | | 1993 | 7,453,057 | | 1992 | 7,246,600 | | 1991 | 6,980,389 | | 1990 | 6,690,462 | | 1989 | 6,375,656 | | 1988 | 6,107,304 | | 1987 | 5,838,927 | | 1986 | 5,578,598 | | 1985 | 5,321,557 | | 1984 | 5,060,011 | | 1983 | 4,809,444 | | 1982 | 4,583,136 | | 1981 | 4,363,814 | | 1980 | 4,181,088 | | 1979 | 4,058,714 | | 1978 | 3,986,023 | | 1977 | 3,945,166 | | 1976 | 3,904,586 | | 1975 | 3,865,489 | | 1974 | 3,831,387 | | 1973 | 3,792,394 | | 1972 | 3,745,720 | | 1971 | 3,696,386 | | 1970 | 3,642,912 | | 1969 | 3,581,831 | | 1968 | 3,511,731 | | 1967 | 3,436,308 | | 1966 | 3,358,684 | | 1965 | 3,286,778 | | 1964 | 3,217,608 | | 1963 | 3,149,739 | | 1962 | 3,081,564 | | 1961 | 3,007,297 | | 1960 | 2,927,085 |
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