| Year | Value | | 2022 | 20,399,026 | | 2021 | 19,935,725 | | 2020 | 19,496,470 | | 2019 | 18,996,934 | | 2018 | 18,522,299 | | 2017 | 18,093,963 | | 2016 | 17,670,436 | | 2015 | 17,220,995 | | 2014 | 16,743,828 | | 2013 | 16,238,262 | | 2012 | 15,716,470 | | 2011 | 15,213,539 | | 2010 | 14,741,778 | | 2009 | 14,298,024 | | 2008 | 13,862,536 | | 2007 | 13,432,342 | | 2006 | 13,002,380 | | 2005 | 12,568,596 | | 2004 | 12,131,185 | | 2003 | 11,692,243 | | 2002 | 11,259,165 | | 2001 | 10,834,726 | | 2000 | 10,424,146 | | 1999 | 10,034,538 | | 1998 | 9,670,933 | | 1997 | 9,329,187 | | 1996 | 9,010,042 | | 1995 | 8,722,385 | | 1994 | 8,465,623 | | 1993 | 8,226,843 | | 1992 | 7,998,742 | | 1991 | 7,778,737 | | 1990 | 7,564,688 | | 1989 | 7,357,515 | | 1988 | 7,159,674 | | 1987 | 6,961,038 | | 1986 | 6,757,063 | | 1985 | 6,544,641 | | 1984 | 6,324,858 | | 1983 | 6,094,944 | | 1982 | 5,858,609 | | 1981 | 5,633,076 | | 1980 | 5,430,932 | | 1979 | 5,246,548 | | 1978 | 5,081,926 | | 1977 | 4,936,522 | | 1976 | 4,785,692 | | 1975 | 4,615,698 | | 1974 | 4,426,808 | | 1973 | 4,212,961 | | 1972 | 3,983,755 | | 1971 | 3,786,093 | | 1970 | 3,642,570 | | 1969 | 3,542,905 | | 1968 | 3,491,994 | | 1967 | 3,478,914 | | 1966 | 3,455,292 | | 1965 | 3,388,788 | | 1964 | 3,275,600 | | 1963 | 3,111,127 | | 1962 | 2,911,557 | | 1961 | 2,722,891 | | 1960 | 2,582,322 |
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