| Year | Value | | 2022 | 40,658,460 | | 2021 | 39,938,624 | | 2020 | 39,150,349 | | 2019 | 38,305,755 | | 2018 | 37,457,726 | | 2017 | 36,648,140 | | 2016 | 35,851,416 | | 2015 | 35,084,711 | | 2014 | 34,371,479 | | 2013 | 33,673,331 | | 2012 | 32,976,860 | | 2011 | 32,297,107 | | 2010 | 31,620,289 | | 2009 | 30,914,246 | | 2008 | 30,190,530 | | 2007 | 29,478,287 | | 2006 | 28,773,282 | | 2005 | 28,071,826 | | 2004 | 27,374,547 | | 2003 | 26,654,692 | | 2002 | 25,888,477 | | 2001 | 25,088,129 | | 2000 | 24,268,857 | | 1999 | 23,442,794 | | 1998 | 22,475,835 | | 1997 | 21,403,175 | | 1996 | 20,394,506 | | 1995 | 19,438,052 | | 1994 | 18,527,914 | | 1993 | 17,831,512 | | 1992 | 17,341,766 | | 1991 | 16,901,146 | | 1990 | 16,526,914 | | 1989 | 16,227,333 | | 1988 | 16,009,306 | | 1987 | 15,845,121 | | 1986 | 15,680,785 | | 1985 | 15,480,252 | | 1984 | 15,239,741 | | 1983 | 14,952,166 | | 1982 | 14,623,600 | | 1981 | 14,289,821 | | 1980 | 13,967,947 | | 1979 | 13,647,293 | | 1978 | 13,318,414 | | 1977 | 12,991,267 | | 1976 | 12,679,417 | | 1975 | 12,386,049 | | 1974 | 12,107,218 | | 1973 | 11,844,365 | | 1972 | 11,599,179 | | 1971 | 11,372,042 | | 1970 | 11,159,801 | | 1969 | 10,963,193 | | 1968 | 10,785,791 | | 1967 | 10,623,293 | | 1966 | 10,465,767 | | 1965 | 10,304,227 | | 1964 | 10,135,545 | | 1963 | 9,957,473 | | 1962 | 9,775,941 | | 1961 | 9,605,454 | | 1960 | 9,452,668 |
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