| Year | Value | | 2022 | 28,160,542 | | 2021 | 27,478,249 | | 2020 | 26,811,790 | | 2019 | 26,147,551 | | 2018 | 25,493,988 | | 2017 | 24,848,016 | | 2016 | 24,213,622 | | 2015 | 23,596,741 | | 2014 | 22,995,555 | | 2013 | 22,469,268 | | 2012 | 22,010,712 | | 2011 | 21,562,914 | | 2010 | 21,120,042 | | 2009 | 20,677,762 | | 2008 | 20,244,449 | | 2007 | 19,817,700 | | 2006 | 19,394,057 | | 2005 | 18,970,215 | | 2004 | 18,544,903 | | 2003 | 18,116,451 | | 2002 | 17,683,897 | | 2001 | 17,245,468 | | 2000 | 16,799,670 | | 1999 | 16,345,894 | | 1998 | 15,858,990 | | 1997 | 15,335,453 | | 1996 | 14,810,946 | | 1995 | 14,299,727 | | 1994 | 13,802,285 | | 1993 | 13,316,448 | | 1992 | 12,838,314 | | 1991 | 12,369,269 | | 1990 | 11,910,540 | | 1989 | 11,462,943 | | 1988 | 11,043,193 | | 1987 | 10,663,498 | | 1986 | 10,309,440 | | 1985 | 9,964,075 | | 1984 | 9,621,405 | | 1983 | 9,282,050 | | 1982 | 8,948,119 | | 1981 | 8,621,621 | | 1980 | 8,303,810 | | 1979 | 7,996,368 | | 1978 | 7,700,816 | | 1977 | 7,415,900 | | 1976 | 7,142,690 | | 1975 | 6,853,981 | | 1974 | 6,548,923 | | 1973 | 6,257,373 | | 1972 | 5,979,984 | | 1971 | 5,718,867 | | 1970 | 5,477,086 | | 1969 | 5,255,149 | | 1968 | 5,050,106 | | 1967 | 4,856,689 | | 1966 | 4,671,196 | | 1965 | 4,492,890 | | 1964 | 4,321,368 | | 1963 | 4,156,453 | | 1962 | 3,998,287 | | 1961 | 3,848,336 | | 1960 | 3,708,661 |
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