| Year | Value | | 2022 | 20,080,697 | | 2021 | 19,188,177 | | 2020 | 18,878,631 | | 2019 | 18,714,847 | | 2018 | 18,319,661 | | 2017 | 17,900,367 | | 2016 | 17,577,957 | | 2015 | 17,204,202 | | 2014 | 16,780,192 | | 2013 | 16,424,913 | | 2012 | 16,106,345 | | 2011 | 15,798,685 | | 2010 | 15,581,672 | | 2009 | 15,446,453 | | 2008 | 15,293,691 | | 2007 | 15,085,752 | | 2006 | 14,825,876 | | 2005 | 14,434,414 | | 2004 | 13,924,420 | | 2003 | 13,475,843 | | 2002 | 13,089,152 | | 2001 | 12,657,812 | | 2000 | 12,315,498 | | 1999 | 11,983,016 | | 1998 | 11,380,757 | | 1997 | 10,647,436 | | 1996 | 10,008,351 | | 1995 | 9,437,201 | | 1994 | 9,130,161 | | 1993 | 9,236,035 | | 1992 | 9,550,651 | | 1991 | 9,814,304 | | 1990 | 9,945,696 | | 1989 | 9,919,552 | | 1988 | 9,766,756 | | 1987 | 9,564,434 | | 1986 | 9,329,122 | | 1985 | 9,104,735 | | 1984 | 8,883,408 | | 1983 | 8,642,904 | | 1982 | 8,424,868 | | 1981 | 8,239,487 | | 1980 | 8,053,951 | | 1979 | 7,847,742 | | 1978 | 7,629,122 | | 1977 | 7,366,067 | | 1976 | 7,087,532 | | 1975 | 6,836,307 | | 1974 | 6,602,124 | | 1973 | 6,402,026 | | 1972 | 6,221,083 | | 1971 | 6,069,371 | | 1970 | 5,944,321 | | 1969 | 5,871,024 | | 1968 | 5,833,695 | | 1967 | 5,798,770 | | 1966 | 5,730,662 | | 1965 | 5,652,286 | | 1964 | 5,571,377 | | 1963 | 5,469,950 | | 1962 | 5,373,872 | | 1961 | 5,282,531 | | 1960 | 5,183,802 |
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