| Year | Value | | 2024 | 557 | | 2023 | 568 | | 2022 | 584 | | 2021 | 600 | | 2020 | 614 | | 2019 | 622 | | 2018 | 627 | | 2017 | 631 | | 2016 | 632 | | 2015 | 642 | | 2014 | 663 | | 2013 | 676 | | 2012 | 690 | | 2011 | 719 | | 2010 | 751 | | 2009 | 772 | | 2008 | 783 | | 2007 | 789 | | 2006 | 788 | | 2005 | 783 | | 2004 | 774 | | 2003 | 757 | | 2002 | 734 | | 2001 | 710 | | 2000 | 684 | | 1999 | 655 | | 1998 | 623 | | 1997 | 592 | | 1996 | 562 | | 1995 | 533 | | 1994 | 505 | | 1993 | 476 | | 1992 | 440 | | 1991 | 404 | | 1990 | 373 | | 1989 | 348 | | 1988 | 332 | | 1987 | 330 | | 1986 | 325 | | 1985 | 305 | | 1984 | 287 | | 1983 | 274 | | 1982 | 262 | | 1981 | 256 | | 1980 | 247 | | 1979 | 234 | | 1978 | 224 | | 1977 | 213 | | 1976 | 205 | | 1975 | 207 |
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