| Year | Value | | 2022 | 20,974,748 | | 2021 | 20,777,426 | | 2020 | 20,526,509 | | 2019 | 20,176,104 | | 2018 | 19,676,733 | | 2017 | 19,147,732 | | 2016 | 18,628,470 | | 2015 | 18,088,683 | | 2014 | 17,514,937 | | 2013 | 16,893,129 | | 2012 | 16,244,256 | | 2011 | 15,624,037 | | 2010 | 15,022,726 | | 2009 | 14,424,619 | | 2008 | 13,864,032 | | 2007 | 13,350,148 | | 2006 | 12,864,171 | | 2005 | 12,425,817 | | 2004 | 12,021,787 | | 2003 | 11,610,859 | | 2002 | 11,215,691 | | 2001 | 10,824,546 | | 2000 | 10,422,498 | | 1999 | 10,043,057 | | 1998 | 9,683,413 | | 1997 | 9,352,857 | | 1996 | 9,072,609 | | 1995 | 8,808,468 | | 1994 | 8,537,847 | | 1993 | 8,301,467 | | 1992 | 8,045,515 | | 1991 | 7,708,002 | | 1990 | 7,359,268 | | 1989 | 7,003,190 | | 1988 | 6,685,842 | | 1987 | 6,366,573 | | 1986 | 6,052,171 | | 1985 | 5,737,784 | | 1984 | 5,413,015 | | 1983 | 5,100,940 | | 1982 | 4,824,660 | | 1981 | 4,547,715 | | 1980 | 4,312,066 | | 1979 | 4,159,333 | | 1978 | 4,063,071 | | 1977 | 4,005,981 | | 1976 | 3,961,436 | | 1975 | 3,926,489 | | 1974 | 3,894,064 | | 1973 | 3,855,855 | | 1972 | 3,811,190 | | 1971 | 3,763,489 | | 1970 | 3,711,040 | | 1969 | 3,649,707 | | 1968 | 3,577,720 | | 1967 | 3,499,698 | | 1966 | 3,420,334 | | 1965 | 3,343,757 | | 1964 | 3,266,725 | | 1963 | 3,192,933 | | 1962 | 3,122,453 | | 1961 | 3,047,431 | | 1960 | 2,968,476 |
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