| Year | Value | | 2022 | 19,521,109 | | 2021 | 19,339,659 | | 2020 | 19,376,846 | | 2019 | 19,392,823 | | 2018 | 19,243,840 | | 2017 | 19,090,816 | | 2016 | 18,937,247 | | 2015 | 18,808,381 | | 2014 | 18,756,412 | | 2013 | 18,787,014 | | 2012 | 18,871,110 | | 2011 | 18,977,364 | | 2010 | 19,028,509 | | 2009 | 18,849,093 | | 2008 | 18,400,753 | | 2007 | 17,760,043 | | 2006 | 17,038,281 | | 2005 | 16,404,658 | | 2004 | 15,979,458 | | 2003 | 15,686,608 | | 2002 | 15,374,864 | | 2001 | 15,012,625 | | 2000 | 14,588,237 | | 1999 | 14,106,967 | | 1998 | 13,604,169 | | 1997 | 13,106,243 | | 1996 | 12,643,309 | | 1995 | 12,235,746 | | 1994 | 11,851,757 | | 1993 | 11,460,808 | | 1992 | 11,117,188 | | 1991 | 10,835,426 | | 1990 | 10,588,824 | | 1989 | 10,255,861 | | 1988 | 9,999,245 | | 1987 | 9,743,529 | | 1986 | 9,450,238 | | 1985 | 9,130,750 | | 1984 | 8,805,362 | | 1983 | 8,469,527 | | 1982 | 8,130,599 | | 1981 | 7,830,108 | | 1980 | 7,558,029 | | 1979 | 7,278,081 | | 1978 | 7,021,356 | | 1977 | 6,781,231 | | 1976 | 6,523,331 | | 1975 | 6,275,889 | | 1974 | 6,033,464 | | 1973 | 5,787,675 | | 1972 | 5,557,311 | | 1971 | 5,337,333 | | 1970 | 5,123,176 | | 1969 | 4,904,699 | | 1968 | 4,680,715 | | 1967 | 4,466,346 | | 1966 | 4,277,581 | | 1965 | 4,124,889 | | 1964 | 4,010,062 | | 1963 | 3,929,739 | | 1962 | 3,876,619 | | 1961 | 3,838,201 | | 1960 | 3,805,348 |
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