| Year | Value | | 2022 | 20,088,470 | | 2021 | 19,749,474 | | 2020 | 19,429,382 | | 2019 | 19,105,246 | | 2018 | 18,772,114 | | 2017 | 18,447,164 | | 2016 | 18,146,160 | | 2015 | 17,870,518 | | 2014 | 17,618,303 | | 2013 | 17,375,463 | | 2012 | 17,113,092 | | 2011 | 16,811,129 | | 2010 | 16,467,981 | | 2009 | 16,096,378 | | 2008 | 15,684,408 | | 2007 | 15,255,225 | | 2006 | 14,821,720 | | 2005 | 14,388,564 | | 2004 | 13,958,227 | | 2003 | 13,534,763 | | 2002 | 13,119,018 | | 2001 | 12,712,161 | | 2000 | 12,316,795 | | 1999 | 11,927,824 | | 1998 | 11,526,483 | | 1997 | 11,110,897 | | 1996 | 10,690,374 | | 1995 | 10,275,580 | | 1994 | 9,882,868 | | 1993 | 9,531,815 | | 1992 | 9,228,156 | | 1991 | 8,962,579 | | 1990 | 8,722,260 | | 1989 | 8,497,677 | | 1988 | 8,286,787 | | 1987 | 8,081,580 | | 1986 | 7,879,722 | | 1985 | 7,678,302 | | 1984 | 7,478,966 | | 1983 | 7,291,438 | | 1982 | 7,122,403 | | 1981 | 6,970,651 | | 1980 | 6,832,530 | | 1979 | 6,702,969 | | 1978 | 6,578,837 | | 1977 | 6,456,522 | | 1976 | 6,329,433 | | 1975 | 6,196,176 | | 1974 | 6,058,825 | | 1973 | 5,913,896 | | 1972 | 5,759,937 | | 1971 | 5,600,070 | | 1970 | 5,439,821 | | 1969 | 5,280,172 | | 1968 | 5,120,981 | | 1967 | 4,970,415 | | 1966 | 4,837,748 | | 1965 | 4,726,745 | | 1964 | 4,634,411 | | 1963 | 4,558,040 | | 1962 | 4,492,521 | | 1961 | 4,427,861 | | 1960 | 4,356,347 |
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