| Year | Value | | 2022 | 17,207,299 | | 2021 | 16,651,123 | | 2020 | 16,095,349 | | 2019 | 15,532,317 | | 2018 | 14,976,917 | | 2017 | 14,443,495 | | 2016 | 13,937,378 | | 2015 | 13,444,550 | | 2014 | 12,960,721 | | 2013 | 12,499,430 | | 2012 | 12,061,397 | | 2011 | 11,651,841 | | 2010 | 11,276,830 | | 2009 | 10,933,348 | | 2008 | 10,621,550 | | 2007 | 10,337,728 | | 2006 | 10,071,172 | | 2005 | 9,809,322 | | 2004 | 9,531,705 | | 2003 | 9,251,849 | | 2002 | 9,008,506 | | 2001 | 8,796,774 | | 2000 | 8,598,011 | | 1999 | 8,420,276 | | 1998 | 8,246,179 | | 1997 | 8,041,331 | | 1996 | 7,819,458 | | 1995 | 7,603,910 | | 1994 | 7,409,023 | | 1993 | 7,240,574 | | 1992 | 7,084,508 | | 1991 | 6,928,425 | | 1990 | 6,770,450 | | 1989 | 6,613,787 | | 1988 | 6,467,596 | | 1987 | 6,327,617 | | 1986 | 6,186,652 | | 1985 | 6,072,015 | | 1984 | 5,976,068 | | 1983 | 5,874,515 | | 1982 | 5,765,453 | | 1981 | 5,648,571 | | 1980 | 5,548,001 | | 1979 | 5,445,121 | | 1978 | 5,316,492 | | 1977 | 5,192,122 | | 1976 | 5,077,873 | | 1975 | 4,962,399 | | 1974 | 4,847,305 | | 1973 | 4,733,011 | | 1972 | 4,620,436 | | 1971 | 4,510,249 | | 1970 | 4,400,782 | | 1969 | 4,296,022 | | 1968 | 4,197,589 | | 1967 | 4,103,751 | | 1966 | 4,012,974 | | 1965 | 3,924,715 | | 1964 | 3,839,160 | | 1963 | 3,757,055 | | 1962 | 3,677,964 | | 1961 | 3,600,386 | | 1960 | 3,526,837 |
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