| Year | Value | | 2022 | 1,124 | | 2021 | 1,078 | | 2020 | 1,050 | | 2019 | 1,029 | | 2018 | 1,012 | | 2017 | 1,010 | | 2016 | 1,021 | | 2015 | 1,043 | | 2014 | 1,065 | | 2013 | 1,077 | | 2012 | 1,077 | | 2011 | 1,074 | | 2010 | 1,073 | | 2009 | 1,066 | | 2008 | 1,053 | | 2007 | 1,038 | | 2006 | 1,020 | | 2005 | 996 | | 2004 | 969 | | 2003 | 947 | | 2002 | 929 | | 2001 | 921 | | 2000 | 926 | | 1999 | 932 | | 1998 | 931 | | 1997 | 923 | | 1996 | 907 | | 1995 | 883 | | 1994 | 858 | | 1993 | 833 | | 1992 | 807 | | 1991 | 781 | | 1990 | 764 | | 1989 | 754 | | 1988 | 745 | | 1987 | 737 | | 1986 | 735 | | 1985 | 737 | | 1984 | 741 | | 1983 | 747 | | 1982 | 754 | | 1981 | 743 | | 1980 | 720 | | 1979 | 699 | | 1978 | 685 | | 1977 | 673 | | 1976 | 661 | | 1975 | 649 | | 1974 | 636 | | 1973 | 618 | | 1972 | 603 | | 1971 | 592 | | 1970 | 584 | | 1969 | 573 | | 1968 | 556 | | 1967 | 536 | | 1966 | 513 | | 1965 | 489 | | 1964 | 466 | | 1963 | 445 | | 1962 | 424 | | 1961 | 404 | | 1960 | 388 |
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