| Year | Value | | 2022 | 2,044 | | 2021 | 1,941 | | 2020 | 1,895 | | 2019 | 1,882 | | 2018 | 1,865 | | 2017 | 1,821 | | 2016 | 1,748 | | 2015 | 1,659 | | 2014 | 1,577 | | 2013 | 1,507 | | 2012 | 1,445 | | 2011 | 1,387 | | 2010 | 1,340 | | 2009 | 1,292 | | 2008 | 1,229 | | 2007 | 1,155 | | 2006 | 1,075 | | 2005 | 1,004 | | 2004 | 950 | | 2003 | 913 | | 2002 | 885 | | 2001 | 858 | | 2000 | 823 | | 1999 | 782 | | 1998 | 739 | | 1997 | 698 | | 1996 | 656 | | 1995 | 616 | | 1994 | 585 | | 1993 | 571 | | 1992 | 573 | | 1991 | 595 | | 1990 | 622 | | 1989 | 636 | | 1988 | 634 | | 1987 | 621 | | 1986 | 601 | | 1985 | 576 | | 1984 | 548 | | 1983 | 523 | | 1982 | 497 | | 1981 | 472 | | 1980 | 447 | | 1979 | 424 | | 1978 | 403 | | 1977 | 378 | | 1976 | 345 | | 1975 | 309 | | 1974 | 272 | | 1973 | 235 | | 1972 | 207 | | 1971 | 202 | | 1970 | 219 | | 1969 | 233 | | 1968 | 235 | | 1967 | 227 | | 1966 | 216 | | 1965 | 205 | | 1964 | 195 | | 1963 | 184 | | 1962 | 174 | | 1961 | 163 | | 1960 | 162 |
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