| Year | Value | | 2022 | 835 | | 2021 | 817 | | 2020 | 806 | | 2019 | 805 | | 2018 | 807 | | 2017 | 818 | | 2016 | 837 | | 2015 | 850 | | 2014 | 854 | | 2013 | 855 | | 2012 | 854 | | 2011 | 845 | | 2010 | 826 | | 2009 | 807 | | 2008 | 791 | | 2007 | 773 | | 2006 | 750 | | 2005 | 723 | | 2004 | 690 | | 2003 | 657 | | 2002 | 630 | | 2001 | 605 | | 2000 | 578 | | 1999 | 561 | | 1998 | 554 | | 1997 | 546 | | 1996 | 538 | | 1995 | 529 | | 1994 | 520 | | 1993 | 510 | | 1992 | 499 | | 1991 | 487 | | 1990 | 474 | | 1989 | 453 | | 1988 | 429 | | 1987 | 406 | | 1986 | 383 | | 1985 | 362 | | 1984 | 343 | | 1983 | 326 | | 1982 | 308 | | 1981 | 287 | | 1980 | 265 | | 1979 | 211 | | 1978 | 146 | | 1977 | 125 | | 1976 | 124 | | 1975 | 128 | | 1974 | 134 | | 1973 | 141 | | 1972 | 147 | | 1971 | 152 | | 1970 | 158 | | 1969 | 164 | | 1968 | 169 | | 1967 | 171 | | 1966 | 173 | | 1965 | 175 | | 1964 | 178 | | 1963 | 180 | | 1962 | 182 | | 1961 | 185 | | 1960 | 188 |
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