| Year | Value | | 2022 | 15,779,228 | | 2021 | 15,522,140 | | 2020 | 15,235,215 | | 2019 | 14,878,294 | | 2018 | 14,472,132 | | 2017 | 14,055,095 | | 2016 | 13,638,919 | | 2015 | 13,223,534 | | 2014 | 12,807,000 | | 2013 | 12,398,206 | | 2012 | 11,998,197 | | 2011 | 11,607,310 | | 2010 | 11,231,860 | | 2009 | 10,873,224 | | 2008 | 10,496,214 | | 2007 | 10,110,751 | | 2006 | 9,724,668 | | 2005 | 9,343,104 | | 2004 | 8,980,991 | | 2003 | 8,657,239 | | 2002 | 8,374,873 | | 2001 | 8,125,997 | | 2000 | 7,899,344 | | 1999 | 7,684,606 | | 1998 | 7,480,804 | | 1997 | 7,282,190 | | 1996 | 7,085,874 | | 1995 | 6,889,150 | | 1994 | 6,693,074 | | 1993 | 6,508,193 | | 1992 | 6,341,151 | | 1991 | 6,189,095 | | 1990 | 6,053,545 | | 1989 | 5,933,803 | | 1988 | 5,821,322 | | 1987 | 5,709,300 | | 1986 | 5,594,303 | | 1985 | 5,474,589 | | 1984 | 5,350,114 | | 1983 | 5,218,012 | | 1982 | 5,078,131 | | 1981 | 4,934,950 | | 1980 | 4,790,646 | | 1979 | 4,643,203 | | 1978 | 4,494,154 | | 1977 | 4,351,744 | | 1976 | 4,223,292 | | 1975 | 4,112,676 | | 1974 | 4,019,734 | | 1973 | 3,942,451 | | 1972 | 3,876,263 | | 1971 | 3,811,790 | | 1970 | 3,744,211 | | 1969 | 3,671,535 | | 1968 | 3,590,583 | | 1967 | 3,502,761 | | 1966 | 3,412,695 | | 1965 | 3,323,776 | | 1964 | 3,237,403 | | 1963 | 3,155,649 | | 1962 | 3,078,117 | | 1961 | 3,001,564 | | 1960 | 2,923,438 |
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