| Year | Value | | 2022 | 18,716,277 | | 2021 | 18,060,788 | | 2020 | 17,427,446 | | 2019 | 16,811,720 | | 2018 | 16,228,957 | | 2017 | 15,673,770 | | 2016 | 15,143,129 | | 2015 | 14,647,922 | | 2014 | 14,183,043 | | 2013 | 13,734,591 | | 2012 | 13,306,286 | | 2011 | 12,889,637 | | 2010 | 12,482,187 | | 2009 | 12,089,493 | | 2008 | 11,702,396 | | 2007 | 11,338,974 | | 2006 | 11,019,957 | | 2005 | 10,717,893 | | 2004 | 10,423,998 | | 2003 | 10,144,745 | | 2002 | 9,860,532 | | 2001 | 9,566,541 | | 2000 | 9,275,926 | | 1999 | 8,963,911 | | 1998 | 8,648,996 | | 1997 | 8,383,942 | | 1996 | 8,165,876 | | 1995 | 7,968,251 | | 1994 | 7,770,015 | | 1993 | 7,570,036 | | 1992 | 7,362,482 | | 1991 | 7,169,970 | | 1990 | 7,008,982 | | 1989 | 6,852,425 | | 1988 | 6,710,775 | | 1987 | 6,590,414 | | 1986 | 6,467,470 | | 1985 | 6,340,287 | | 1984 | 6,208,144 | | 1983 | 6,072,527 | | 1982 | 5,939,894 | | 1981 | 5,830,846 | | 1980 | 5,734,601 | | 1979 | 5,621,012 | | 1978 | 5,494,371 | | 1977 | 5,370,360 | | 1976 | 5,254,562 | | 1975 | 5,138,492 | | 1974 | 5,021,697 | | 1973 | 4,907,296 | | 1972 | 4,797,830 | | 1971 | 4,693,205 | | 1970 | 4,590,218 | | 1969 | 4,492,569 | | 1968 | 4,398,658 | | 1967 | 4,305,417 | | 1966 | 4,213,656 | | 1965 | 4,121,004 | | 1964 | 4,027,481 | | 1963 | 3,937,298 | | 1962 | 3,851,250 | | 1961 | 3,768,053 | | 1960 | 3,690,659 |
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