Year | Value | 2022 | 18,514,605 | 2021 | 18,418,497 | 2020 | 18,086,714 | 2019 | 17,806,516 | 2018 | 17,474,844 | 2017 | 17,186,558 | 2016 | 17,002,455 | 2015 | 16,822,707 | 2014 | 16,620,302 | 2013 | 16,420,396 | 2012 | 16,223,051 | 2011 | 16,014,091 | 2010 | 15,762,674 | 2009 | 15,506,774 | 2008 | 15,327,568 | 2007 | 15,186,090 | 2006 | 15,027,592 | 2005 | 14,918,275 | 2004 | 14,939,718 | 2003 | 15,068,351 | 2002 | 15,296,582 | 2001 | 15,675,260 | 2000 | 16,136,947 | 1999 | 16,552,561 | 1998 | 16,810,426 | 1997 | 16,936,972 | 1996 | 16,946,637 | 1995 | 16,840,865 | 1994 | 16,728,674 | 1993 | 16,596,858 | 1992 | 16,382,703 | 1991 | 16,123,018 | 1990 | 15,832,143 | 1989 | 15,554,992 | 1988 | 15,171,518 | 1987 | 14,649,982 | 1986 | 14,064,851 | 1985 | 13,126,386 | 1984 | 11,819,258 | 1983 | 10,578,931 | 1982 | 9,697,685 | 1981 | 9,412,810 | 1980 | 9,888,842 | 1979 | 10,954,615 | 1978 | 12,296,212 | 1977 | 13,570,313 | 1976 | 14,269,341 | 1975 | 14,348,443 | 1974 | 13,964,073 | 1973 | 13,230,133 | 1972 | 12,541,740 | 1971 | 12,093,978 | 1970 | 12,063,667 | 1969 | 12,448,551 | 1968 | 13,071,275 | 1967 | 13,567,947 | 1966 | 13,853,773 | 1965 | 13,939,794 | 1964 | 13,750,278 | 1963 | 13,343,643 | 1962 | 12,764,608 | 1961 | 12,026,482 | 1960 | 11,180,358 |
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