| Year | Value | | 2022 | 22,838,982 | | 2021 | 21,952,710 | | 2020 | 21,489,863 | | 2019 | 21,022,093 | | 2018 | 20,528,499 | | 2017 | 20,128,617 | | 2016 | 19,691,555 | | 2015 | 19,252,233 | | 2014 | 18,942,232 | | 2013 | 18,669,553 | | 2012 | 18,259,722 | | 2011 | 17,712,994 | | 2010 | 17,145,426 | | 2009 | 16,574,427 | | 2008 | 15,963,712 | | 2007 | 15,382,501 | | 2006 | 14,857,997 | | 2005 | 14,332,454 | | 2004 | 13,821,203 | | 2003 | 13,269,723 | | 2002 | 12,645,862 | | 2001 | 12,052,169 | | 2000 | 11,466,472 | | 1999 | 10,833,660 | | 1998 | 10,225,057 | | 1997 | 9,716,324 | | 1996 | 9,279,931 | | 1995 | 8,876,887 | | 1994 | 8,563,857 | | 1993 | 8,349,430 | | 1992 | 8,124,419 | | 1991 | 7,851,754 | | 1990 | 7,568,441 | | 1989 | 7,265,652 | | 1988 | 6,935,616 | | 1987 | 6,630,285 | | 1986 | 6,361,974 | | 1985 | 6,106,378 | | 1984 | 5,846,304 | | 1983 | 5,607,766 | | 1982 | 5,405,274 | | 1981 | 5,217,952 | | 1980 | 5,028,569 | | 1979 | 4,812,811 | | 1978 | 4,566,345 | | 1977 | 4,317,355 | | 1976 | 4,081,420 | | 1975 | 3,869,592 | | 1974 | 3,701,230 | | 1973 | 3,552,105 | | 1972 | 3,403,549 | | 1971 | 3,262,046 | | 1970 | 3,122,062 | | 1969 | 3,010,941 | | 1968 | 2,922,205 | | 1967 | 2,840,642 | | 1966 | 2,772,256 | | 1965 | 2,722,429 | | 1964 | 2,666,716 | | 1963 | 2,597,588 | | 1962 | 2,537,771 | | 1961 | 2,525,651 | | 1960 | 2,587,897 |
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