| Year | Value | | 2022 | 1,747 | | 2021 | 1,697 | | 2020 | 1,643 | | 2019 | 1,586 | | 2018 | 1,521 | | 2017 | 1,459 | | 2016 | 1,412 | | 2015 | 1,375 | | 2014 | 1,342 | | 2013 | 1,313 | | 2012 | 1,286 | | 2011 | 1,254 | | 2010 | 1,219 | | 2009 | 1,174 | | 2008 | 1,125 | | 2007 | 1,087 | | 2006 | 1,058 | | 2005 | 1,034 | | 2004 | 1,014 | | 2003 | 997 | | 2002 | 982 | | 2001 | 964 | | 2000 | 941 | | 1999 | 924 | | 1998 | 916 | | 1997 | 908 | | 1996 | 901 | | 1995 | 898 | | 1994 | 894 | | 1993 | 892 | | 1992 | 890 | | 1991 | 883 | | 1990 | 874 | | 1989 | 851 | | 1988 | 817 | | 1987 | 785 | | 1986 | 754 | | 1985 | 726 | | 1984 | 701 | | 1983 | 678 | | 1982 | 656 | | 1981 | 635 | | 1980 | 616 | | 1979 | 488 | | 1978 | 330 | | 1977 | 296 | | 1976 | 306 | | 1975 | 314 | | 1974 | 324 | | 1973 | 332 | | 1972 | 340 | | 1971 | 351 | | 1970 | 363 | | 1969 | 376 | | 1968 | 389 | | 1967 | 399 | | 1966 | 405 | | 1965 | 411 | | 1964 | 417 | | 1963 | 424 | | 1962 | 430 | | 1961 | 438 | | 1960 | 446 |
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