| Year | Value | | 2024 | 789 | | 2023 | 781 | | 2022 | 772 | | 2021 | 768 | | 2020 | 763 | | 2019 | 756 | | 2018 | 749 | | 2017 | 740 | | 2016 | 724 | | 2015 | 709 | | 2014 | 694 | | 2013 | 674 | | 2012 | 664 | | 2011 | 674 | | 2010 | 682 | | 2009 | 684 | | 2008 | 680 | | 2007 | 668 | | 2006 | 649 | | 2005 | 627 | | 2004 | 607 | | 2003 | 587 | | 2002 | 567 | | 2001 | 547 | | 2000 | 523 | | 1999 | 489 | | 1998 | 447 | | 1997 | 407 | | 1996 | 370 | | 1995 | 340 | | 1994 | 324 | | 1993 | 314 | | 1992 | 306 | | 1991 | 296 | | 1990 | 283 | | 1989 | 265 | | 1988 | 244 | | 1987 | 220 | | 1986 | 196 | | 1985 | 184 | | 1984 | 180 | | 1983 | 178 | | 1982 | 179 | | 1981 | 184 | | 1980 | 189 | | 1979 | 195 | | 1978 | 201 | | 1977 | 207 | | 1976 | 215 | | 1975 | 223 |
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