| Year | Value | | 2022 | 18,141,175 | | 2021 | 17,816,242 | | 2020 | 17,504,438 | | 2019 | 17,187,483 | | 2018 | 16,852,247 | | 2017 | 16,524,782 | | 2016 | 16,233,523 | | 2015 | 15,973,860 | | 2014 | 15,739,170 | | 2013 | 15,515,134 | | 2012 | 15,274,179 | | 2011 | 14,996,092 | | 2010 | 14,680,321 | | 2009 | 14,339,889 | | 2008 | 13,960,947 | | 2007 | 13,566,930 | | 2006 | 13,170,681 | | 2005 | 12,777,957 | | 2004 | 12,391,244 | | 2003 | 12,014,021 | | 2002 | 11,647,210 | | 2001 | 11,290,063 | | 2000 | 10,942,439 | | 1999 | 10,599,813 | | 1998 | 10,244,630 | | 1997 | 9,873,463 | | 1996 | 9,496,363 | | 1995 | 9,125,670 | | 1994 | 8,775,676 | | 1993 | 8,464,390 | | 1992 | 8,199,342 | | 1991 | 7,970,215 | | 1990 | 7,761,711 | | 1989 | 7,566,539 | | 1988 | 7,383,463 | | 1987 | 7,202,905 | | 1986 | 7,022,174 | | 1985 | 6,838,462 | | 1984 | 6,654,752 | | 1983 | 6,481,684 | | 1982 | 6,325,386 | | 1981 | 6,184,725 | | 1980 | 6,056,497 | | 1979 | 5,935,321 | | 1978 | 5,817,530 | | 1977 | 5,701,783 | | 1976 | 5,583,445 | | 1975 | 5,462,363 | | 1974 | 5,341,093 | | 1973 | 5,216,323 | | 1972 | 5,085,441 | | 1971 | 4,948,814 | | 1970 | 4,810,085 | | 1969 | 4,669,109 | | 1968 | 4,525,998 | | 1967 | 4,389,452 | | 1966 | 4,269,278 | | 1965 | 4,169,759 | | 1964 | 4,087,680 | | 1963 | 4,019,692 | | 1962 | 3,961,594 | | 1961 | 3,904,810 | | 1960 | 3,842,478 |
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