| Year | Value | | 2022 | 1,929 | | 2021 | 1,898 | | 2020 | 1,836 | | 2019 | 1,767 | | 2018 | 1,716 | | 2017 | 1,667 | | 2016 | 1,614 | | 2015 | 1,560 | | 2014 | 1,506 | | 2013 | 1,447 | | 2012 | 1,383 | | 2011 | 1,316 | | 2010 | 1,247 | | 2009 | 1,173 | | 2008 | 1,104 | | 2007 | 1,046 | | 2006 | 999 | | 2005 | 955 | | 2004 | 916 | | 2003 | 886 | | 2002 | 864 | | 2001 | 844 | | 2000 | 820 | | 1999 | 798 | | 1998 | 788 | | 1997 | 786 | | 1996 | 790 | | 1995 | 803 | | 1994 | 824 | | 1993 | 846 | | 1992 | 865 | | 1991 | 864 | | 1990 | 837 | | 1989 | 797 | | 1988 | 760 | | 1987 | 729 | | 1986 | 705 | | 1985 | 689 | | 1984 | 675 | | 1983 | 663 | | 1982 | 651 | | 1981 | 635 | | 1980 | 618 | | 1979 | 596 | | 1978 | 571 | | 1977 | 545 | | 1976 | 522 | | 1975 | 504 | | 1974 | 486 | | 1973 | 470 | | 1972 | 454 | | 1971 | 440 | | 1970 | 426 | | 1969 | 412 | | 1968 | 399 | | 1967 | 385 | | 1966 | 368 | | 1965 | 350 | | 1964 | 332 | | 1963 | 315 | | 1962 | 296 | | 1961 | 276 | | 1960 | 254 |
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