| Year | Value | | 2022 | 1,691 | | 2021 | 1,637 | | 2020 | 1,585 | | 2019 | 1,540 | | 2018 | 1,512 | | 2017 | 1,489 | | 2016 | 1,467 | | 2015 | 1,441 | | 2014 | 1,411 | | 2013 | 1,376 | | 2012 | 1,340 | | 2011 | 1,314 | | 2010 | 1,300 | | 2009 | 1,273 | | 2008 | 1,229 | | 2007 | 1,190 | | 2006 | 1,152 | | 2005 | 1,117 | | 2004 | 1,085 | | 2003 | 1,050 | | 2002 | 1,007 | | 2001 | 955 | | 2000 | 899 | | 1999 | 843 | | 1998 | 790 | | 1997 | 741 | | 1996 | 693 | | 1995 | 652 | | 1994 | 631 | | 1993 | 635 | | 1992 | 659 | | 1991 | 680 | | 1990 | 693 | | 1989 | 702 | | 1988 | 702 | | 1987 | 690 | | 1986 | 671 | | 1985 | 648 | | 1984 | 626 | | 1983 | 606 | | 1982 | 588 | | 1981 | 573 | | 1980 | 557 | | 1979 | 545 | | 1978 | 538 | | 1977 | 528 | | 1976 | 514 | | 1975 | 497 | | 1974 | 479 | | 1973 | 462 | | 1972 | 444 | | 1971 | 429 | | 1970 | 418 | | 1969 | 405 | | 1968 | 393 | | 1967 | 381 | | 1966 | 370 | | 1965 | 361 | | 1964 | 354 | | 1963 | 349 | | 1962 | 344 | | 1961 | 338 | | 1960 | 328 |
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