| Year | Value | | 2022 | 1,968 | | 2021 | 1,973 | | 2020 | 1,967 | | 2019 | 1,951 | | 2018 | 1,927 | | 2017 | 1,891 | | 2016 | 1,848 | | 2015 | 1,799 | | 2014 | 1,746 | | 2013 | 1,691 | | 2012 | 1,634 | | 2011 | 1,567 | | 2010 | 1,495 | | 2009 | 1,423 | | 2008 | 1,355 | | 2007 | 1,291 | | 2006 | 1,236 | | 2005 | 1,197 | | 2004 | 1,172 | | 2003 | 1,156 | | 2002 | 1,143 | | 2001 | 1,131 | | 2000 | 1,115 | | 1999 | 1,093 | | 1998 | 1,069 | | 1997 | 1,042 | | 1996 | 1,017 | | 1995 | 995 | | 1994 | 979 | | 1993 | 967 | | 1992 | 959 | | 1991 | 952 | | 1990 | 945 | | 1989 | 940 | | 1988 | 930 | | 1987 | 917 | | 1986 | 901 | | 1985 | 885 | | 1984 | 871 | | 1983 | 860 | | 1982 | 852 | | 1981 | 845 | | 1980 | 836 | | 1979 | 830 | | 1978 | 827 | | 1977 | 819 | | 1976 | 807 | | 1975 | 796 | | 1974 | 791 | | 1973 | 794 | | 1972 | 798 | | 1971 | 799 | | 1970 | 796 | | 1969 | 785 | | 1968 | 765 | | 1967 | 742 | | 1966 | 717 | | 1965 | 690 | | 1964 | 663 | | 1963 | 636 | | 1962 | 614 | | 1961 | 596 | | 1960 | 576 |
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