| Year | Value | | 2024 | 513 | | 2023 | 489 | | 2022 | 476 | | 2021 | 484 | | 2020 | 513 | | 2019 | 568 | | 2018 | 629 | | 2017 | 673 | | 2016 | 693 | | 2015 | 695 | | 2014 | 680 | | 2013 | 640 | | 2012 | 617 | | 2011 | 627 | | 2010 | 636 | | 2009 | 645 | | 2008 | 656 | | 2007 | 669 | | 2006 | 686 | | 2005 | 708 | | 2004 | 737 | | 2003 | 757 | | 2002 | 758 | | 2001 | 748 | | 2000 | 746 | | 1999 | 767 | | 1998 | 789 | | 1997 | 788 | | 1996 | 767 | | 1995 | 757 | | 1994 | 777 | | 1993 | 796 | | 1992 | 796 | | 1991 | 777 | | 1990 | 757 | | 1989 | 763 | | 1988 | 794 | | 1987 | 821 | | 1986 | 829 | | 1985 | 817 | | 1984 | 790 | | 1983 | 753 | | 1982 | 707 | | 1981 | 660 | | 1980 | 624 | | 1979 | 606 | | 1978 | 608 | | 1977 | 618 | | 1976 | 623 | | 1975 | 628 |
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