| Year | Value | | 2022 | 19,057,108 | | 2021 | 18,729,623 | | 2020 | 18,408,720 | | 2019 | 18,084,515 | | 2018 | 17,750,706 | | 2017 | 17,426,344 | | 2016 | 17,132,324 | | 2015 | 16,871,630 | | 2014 | 16,640,006 | | 2013 | 16,416,504 | | 2012 | 16,173,185 | | 2011 | 15,891,698 | | 2010 | 15,565,715 | | 2009 | 15,207,282 | | 2008 | 14,806,870 | | 2007 | 14,389,026 | | 2006 | 13,966,588 | | 2005 | 13,544,878 | | 2004 | 13,126,003 | | 2003 | 12,714,251 | | 2002 | 12,312,054 | | 2001 | 11,920,845 | | 2000 | 11,542,650 | | 1999 | 11,172,924 | | 1998 | 10,792,493 | | 1997 | 10,395,711 | | 1996 | 9,992,663 | | 1995 | 9,584,847 | | 1994 | 9,186,993 | | 1993 | 8,828,158 | | 1992 | 8,515,919 | | 1991 | 8,241,193 | | 1990 | 8,000,604 | | 1989 | 7,790,420 | | 1988 | 7,600,461 | | 1987 | 7,418,822 | | 1986 | 7,242,516 | | 1985 | 7,069,899 | | 1984 | 6,901,986 | | 1983 | 6,745,202 | | 1982 | 6,603,841 | | 1981 | 6,475,149 | | 1980 | 6,354,137 | | 1979 | 6,236,444 | | 1978 | 6,118,123 | | 1977 | 5,994,588 | | 1976 | 5,863,629 | | 1975 | 5,724,785 | | 1974 | 5,577,469 | | 1973 | 5,421,468 | | 1972 | 5,258,577 | | 1971 | 5,092,135 | | 1970 | 4,923,026 | | 1969 | 4,752,161 | | 1968 | 4,583,619 | | 1967 | 4,426,108 | | 1966 | 4,289,328 | | 1965 | 4,177,262 | | 1964 | 4,086,958 | | 1963 | 4,014,150 | | 1962 | 3,951,171 | | 1961 | 3,886,471 | | 1960 | 3,812,934 |
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