| Year | Value | | 2022 | 32,370,931 | | 2021 | 31,417,653 | | 2020 | 30,475,454 | | 2019 | 29,563,439 | | 2018 | 28,679,332 | | 2017 | 27,762,906 | | 2016 | 26,813,222 | | 2015 | 25,860,541 | | 2014 | 24,985,511 | | 2013 | 24,210,106 | | 2012 | 23,483,484 | | 2011 | 22,811,421 | | 2010 | 22,176,064 | | 2009 | 21,632,887 | | 2008 | 21,125,684 | | 2007 | 20,570,092 | | 2006 | 20,010,132 | | 2005 | 19,465,727 | | 2004 | 18,943,000 | | 2003 | 18,446,378 | | 2002 | 17,969,988 | | 2001 | 17,511,199 | | 2000 | 17,040,809 | | 1999 | 16,558,330 | | 1998 | 16,126,609 | | 1997 | 15,711,433 | | 1996 | 15,413,954 | | 1995 | 15,155,265 | | 1994 | 14,665,108 | | 1993 | 14,071,279 | | 1992 | 13,620,921 | | 1991 | 13,289,463 | | 1990 | 12,959,424 | | 1989 | 12,629,638 | | 1988 | 12,311,736 | | 1987 | 11,941,483 | | 1986 | 11,539,360 | | 1985 | 11,149,999 | | 1984 | 10,792,604 | | 1983 | 10,453,409 | | 1982 | 10,122,567 | | 1981 | 9,839,040 | | 1980 | 9,563,367 | | 1979 | 9,276,749 | | 1978 | 8,970,688 | | 1977 | 8,658,410 | | 1976 | 8,349,751 | | 1975 | 8,051,052 | | 1974 | 7,763,717 | | 1973 | 7,488,842 | | 1972 | 7,223,324 | | 1971 | 6,970,017 | | 1970 | 6,732,259 | | 1969 | 6,506,341 | | 1968 | 6,291,463 | | 1967 | 6,094,257 | | 1966 | 5,912,208 | | 1965 | 5,736,305 | | 1964 | 5,565,091 | | 1963 | 5,399,570 | | 1962 | 5,241,093 | | 1961 | 5,086,813 | | 1960 | 4,938,264 |
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