| Year | Value | | 2022 | 16,122,139 | | 2021 | 16,224,503 | | 2020 | 16,361,163 | | 2019 | 16,475,071 | | 2018 | 16,556,710 | | 2017 | 16,638,462 | | 2016 | 16,726,681 | | 2015 | 16,810,594 | | 2014 | 16,869,537 | | 2013 | 16,848,052 | | 2012 | 16,716,076 | | 2011 | 16,481,389 | | 2010 | 16,128,346 | | 2009 | 15,679,403 | | 2008 | 15,193,919 | | 2007 | 14,646,139 | | 2006 | 14,066,609 | | 2005 | 13,508,251 | | 2004 | 12,960,033 | | 2003 | 12,446,613 | | 2002 | 12,024,956 | | 2001 | 11,643,684 | | 2000 | 11,268,709 | | 1999 | 10,946,470 | | 1998 | 10,663,398 | | 1997 | 10,393,654 | | 1996 | 10,132,678 | | 1995 | 9,885,333 | | 1994 | 9,645,505 | | 1993 | 9,460,763 | | 1992 | 9,276,704 | | 1991 | 9,011,969 | | 1990 | 8,671,360 | | 1989 | 8,269,554 | | 1988 | 7,990,395 | | 1987 | 7,708,750 | | 1986 | 7,443,858 | | 1985 | 7,204,488 | | 1984 | 6,974,442 | | 1983 | 6,752,590 | | 1982 | 6,540,202 | | 1981 | 6,281,299 | | 1980 | 6,013,255 | | 1979 | 5,789,069 | | 1978 | 5,575,285 | | 1977 | 5,359,244 | | 1976 | 5,127,611 | | 1975 | 4,896,680 | | 1974 | 4,674,136 | | 1973 | 4,465,307 | | 1972 | 4,278,536 | | 1971 | 4,113,858 | | 1970 | 3,979,065 | | 1969 | 3,879,278 | | 1968 | 3,814,994 | | 1967 | 3,778,746 | | 1966 | 3,757,580 | | 1965 | 3,737,066 | | 1964 | 3,711,972 | | 1963 | 3,680,765 | | 1962 | 3,642,021 | | 1961 | 3,599,138 | | 1960 | 3,558,825 |
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