| Year | Value | | 2022 | 19,068,848 | | 2021 | 18,792,371 | | 2020 | 18,543,098 | | 2019 | 18,298,234 | | 2018 | 18,050,077 | | 2017 | 17,782,984 | | 2016 | 17,471,889 | | 2015 | 17,112,024 | | 2014 | 16,705,078 | | 2013 | 16,261,283 | | 2012 | 15,796,120 | | 2011 | 15,324,726 | | 2010 | 14,856,388 | | 2009 | 14,401,442 | | 2008 | 13,944,348 | | 2007 | 13,496,749 | | 2006 | 13,060,663 | | 2005 | 12,638,408 | | 2004 | 12,224,622 | | 2003 | 11,799,262 | | 2002 | 11,361,573 | | 2001 | 10,921,813 | | 2000 | 10,478,005 | | 1999 | 10,044,859 | | 1998 | 9,652,507 | | 1997 | 9,306,291 | | 1996 | 8,998,237 | | 1995 | 8,728,476 | | 1994 | 8,488,599 | | 1993 | 8,266,819 | | 1992 | 8,055,436 | | 1991 | 7,851,706 | | 1990 | 7,654,769 | | 1989 | 7,470,108 | | 1988 | 7,304,215 | | 1987 | 7,154,747 | | 1986 | 7,017,030 | | 1985 | 6,887,661 | | 1984 | 6,762,604 | | 1983 | 6,636,162 | | 1982 | 6,503,590 | | 1981 | 6,361,063 | | 1980 | 6,206,712 | | 1979 | 6,041,421 | | 1978 | 5,866,044 | | 1977 | 5,682,055 | | 1976 | 5,497,269 | | 1975 | 5,314,833 | | 1974 | 5,132,112 | | 1973 | 4,950,605 | | 1972 | 4,778,960 | | 1971 | 4,627,266 | | 1970 | 4,502,067 | | 1969 | 4,402,173 | | 1968 | 4,321,975 | | 1967 | 4,253,110 | | 1966 | 4,183,058 | | 1965 | 4,102,117 | | 1964 | 4,007,478 | | 1963 | 3,899,010 | | 1962 | 3,779,647 | | 1961 | 3,657,238 | | 1960 | 3,538,686 |
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