| Year | Value | | 2022 | 24,196,351 | | 2021 | 23,753,114 | | 2020 | 23,309,111 | | 2019 | 22,869,599 | | 2018 | 22,437,808 | | 2017 | 21,994,745 | | 2016 | 21,541,817 | | 2015 | 21,088,840 | | 2014 | 20,636,838 | | 2013 | 20,180,706 | | 2012 | 19,725,140 | | 2011 | 19,275,316 | | 2010 | 18,835,465 | | 2009 | 18,409,274 | | 2008 | 17,995,882 | | 2007 | 17,589,282 | | 2006 | 17,188,176 | | 2005 | 16,790,498 | | 2004 | 16,411,301 | | 2003 | 16,111,112 | | 2002 | 15,820,051 | | 2001 | 15,524,469 | | 2000 | 15,229,497 | | 1999 | 14,935,781 | | 1998 | 14,640,178 | | 1997 | 14,342,391 | | 1996 | 14,045,468 | | 1995 | 13,749,580 | | 1994 | 13,440,086 | | 1993 | 13,050,229 | | 1992 | 12,660,713 | | 1991 | 12,273,397 | | 1990 | 11,890,063 | | 1989 | 11,510,435 | | 1988 | 11,135,157 | | 1987 | 10,759,753 | | 1986 | 10,384,666 | | 1985 | 10,001,424 | | 1984 | 9,613,344 | | 1983 | 9,227,441 | | 1982 | 8,845,176 | | 1981 | 8,471,303 | | 1980 | 8,109,487 | | 1979 | 7,763,286 | | 1978 | 7,434,210 | | 1977 | 7,118,548 | | 1976 | 6,819,390 | | 1975 | 6,534,073 | | 1974 | 6,258,783 | | 1973 | 5,993,751 | | 1972 | 5,737,053 | | 1971 | 5,488,936 | | 1970 | 5,266,138 | | 1969 | 5,050,140 | | 1968 | 4,842,439 | | 1967 | 4,641,545 | | 1966 | 4,448,115 | | 1965 | 4,263,735 | | 1964 | 4,089,765 | | 1963 | 3,925,674 | | 1962 | 3,764,224 | | 1961 | 3,606,271 | | 1960 | 3,455,253 |
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