| Year | Value | | 2022 | 22,125,249 | | 2021 | 21,324,367 | | 2020 | 20,772,595 | | 2019 | 20,098,251 | | 2018 | 19,333,463 | | 2017 | 18,983,373 | | 2016 | 18,964,252 | | 2015 | 19,205,178 | | 2014 | 20,072,232 | | 2013 | 21,495,821 | | 2012 | 22,605,577 | | 2011 | 22,730,733 | | 2010 | 22,337,563 | | 2009 | 21,827,220 | | 2008 | 21,474,059 | | 2007 | 20,703,005 | | 2006 | 19,432,009 | | 2005 | 18,583,557 | | 2004 | 18,084,007 | | 2003 | 17,611,356 | | 2002 | 17,164,021 | | 2001 | 16,727,948 | | 2000 | 16,307,654 | | 1999 | 15,901,201 | | 1998 | 15,500,542 | | 1997 | 15,103,996 | | 1996 | 14,708,879 | | 1995 | 14,313,450 | | 1994 | 13,922,626 | | 1993 | 13,537,060 | | 1992 | 13,156,406 | | 1991 | 12,782,281 | | 1990 | 12,408,996 | | 1989 | 12,034,097 | | 1988 | 11,657,772 | | 1987 | 11,281,107 | | 1986 | 10,907,619 | | 1985 | 10,540,926 | | 1984 | 10,183,138 | | 1983 | 9,835,461 | | 1982 | 9,510,754 | | 1981 | 9,203,635 | | 1980 | 8,898,954 | | 1979 | 8,600,747 | | 1978 | 8,310,217 | | 1977 | 8,029,313 | | 1976 | 7,758,673 | | 1975 | 7,497,126 | | 1974 | 7,244,901 | | 1973 | 7,003,114 | | 1972 | 6,768,544 | | 1971 | 6,538,526 | | 1970 | 6,319,199 | | 1969 | 6,111,364 | | 1968 | 5,912,715 | | 1967 | 5,723,306 | | 1966 | 5,542,003 | | 1965 | 5,368,451 | | 1964 | 5,202,846 | | 1963 | 5,045,245 | | 1962 | 4,894,995 | | 1961 | 4,751,534 | | 1960 | 4,610,712 |
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