| Year | Value | | 2022 | 1,266 | | 2021 | 1,007 | | 2020 | 966 | | 2019 | 931 | | 2018 | 915 | | 2017 | 912 | | 2016 | 903 | | 2015 | 889 | | 2014 | 870 | | 2013 | 862 | | 2012 | 863 | | 2011 | 882 | | 2010 | 935 | | 2009 | 928 | | 2008 | 937 | | 2007 | 923 | | 2006 | 921 | | 2005 | 908 | | 2004 | 917 | | 2003 | 939 | | 2002 | 962 | | 2001 | 935 | | 2000 | 929 | | 1999 | 907 | | 1998 | 873 | | 1997 | 853 | | 1996 | 844 | | 1995 | 823 | | 1994 | 805 | | 1993 | 779 | | 1992 | 752 | | 1991 | 743 | | 1990 | 731 | | 1989 | 723 | | 1988 | 712 | | 1987 | 702 | | 1986 | 665 | | 1985 | 654 | | 1984 | 647 | | 1983 | 642 | | 1982 | 640 | | 1981 | 633 | | 1980 | 624 | | 1979 | 616 | | 1978 | 608 | | 1977 | 604 | | 1976 | 594 | | 1975 | 584 | | 1974 | 569 | | 1973 | 557 | | 1972 | 547 | | 1971 | 529 | | 1970 | 508 | | 1969 | 486 | | 1968 | 467 | | 1967 | 452 | | 1966 | 442 | | 1965 | 436 | | 1964 | 429 | | 1963 | 424 | | 1962 | 416 | | 1961 | 403 | | 1960 | 390 |
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