| Year | Value | | 2022 | 1,292 | | 2021 | 1,286 | | 2020 | 1,276 | | 2019 | 1,248 | | 2018 | 1,201 | | 2017 | 1,140 | | 2016 | 1,072 | | 2015 | 1,007 | | 2014 | 950 | | 2013 | 909 | | 2012 | 887 | | 2011 | 883 | | 2010 | 881 | | 2009 | 868 | | 2008 | 849 | | 2007 | 819 | | 2006 | 779 | | 2005 | 747 | | 2004 | 731 | | 2003 | 716 | | 2002 | 706 | | 2001 | 709 | | 2000 | 712 | | 1999 | 708 | | 1998 | 703 | | 1997 | 694 | | 1996 | 682 | | 1995 | 675 | | 1994 | 673 | | 1993 | 664 | | 1992 | 646 | | 1991 | 621 | | 1990 | 600 | | 1989 | 584 | | 1988 | 567 | | 1987 | 557 | | 1986 | 557 | | 1985 | 558 | | 1984 | 559 | | 1983 | 559 | | 1982 | 554 | | 1981 | 542 | | 1980 | 529 | | 1979 | 511 | | 1978 | 503 | | 1977 | 507 | | 1976 | 502 | | 1975 | 498 | | 1974 | 504 | | 1973 | 520 | | 1972 | 537 | | 1971 | 546 | | 1970 | 541 | | 1969 | 521 | | 1968 | 513 | | 1967 | 517 | | 1966 | 511 | | 1965 | 495 | | 1964 | 471 | | 1963 | 450 | | 1962 | 440 | | 1961 | 438 | | 1960 | 442 |
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