| Year | Value | | 2022 | 1,589 | | 2021 | 1,502 | | 2020 | 1,440 | | 2019 | 1,405 | | 2018 | 1,397 | | 2017 | 1,405 | | 2016 | 1,420 | | 2015 | 1,439 | | 2014 | 1,457 | | 2013 | 1,466 | | 2012 | 1,464 | | 2011 | 1,446 | | 2010 | 1,415 | | 2009 | 1,376 | | 2008 | 1,333 | | 2007 | 1,294 | | 2006 | 1,270 | | 2005 | 1,258 | | 2004 | 1,260 | | 2003 | 1,268 | | 2002 | 1,275 | | 2001 | 1,283 | | 2000 | 1,290 | | 1999 | 1,292 | | 1998 | 1,287 | | 1997 | 1,270 | | 1996 | 1,230 | | 1995 | 1,171 | | 1994 | 1,095 | | 1993 | 1,013 | | 1992 | 933 | | 1991 | 862 | | 1990 | 803 | | 1989 | 759 | | 1988 | 733 | | 1987 | 722 | | 1986 | 728 | | 1985 | 734 | | 1984 | 725 | | 1983 | 706 | | 1982 | 682 | | 1981 | 678 | | 1980 | 686 | | 1979 | 679 | | 1978 | 659 | | 1977 | 634 | | 1976 | 627 | | 1975 | 638 | | 1974 | 641 | | 1973 | 635 | | 1972 | 629 | | 1971 | 625 | | 1970 | 620 | | 1969 | 616 | | 1968 | 614 | | 1967 | 610 | | 1966 | 583 | | 1965 | 542 | | 1964 | 509 | | 1963 | 478 | | 1962 | 446 | | 1961 | 428 | | 1960 | 420 |
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