| Year | Value | | 2022 | 1,893 | | 2021 | 1,863 | | 2020 | 1,818 | | 2019 | 1,750 | | 2018 | 1,663 | | 2017 | 1,570 | | 2016 | 1,474 | | 2015 | 1,384 | | 2014 | 1,306 | | 2013 | 1,240 | | 2012 | 1,180 | | 2011 | 1,128 | | 2010 | 1,080 | | 2009 | 1,033 | | 2008 | 987 | | 2007 | 946 | | 2006 | 912 | | 2005 | 877 | | 2004 | 835 | | 2003 | 786 | | 2002 | 737 | | 2001 | 690 | | 2000 | 655 | | 1999 | 635 | | 1998 | 622 | | 1997 | 619 | | 1996 | 618 | | 1995 | 603 | | 1994 | 587 | | 1993 | 567 | | 1992 | 536 | | 1991 | 504 | | 1990 | 482 | | 1989 | 449 | | 1988 | 423 | | 1987 | 393 | | 1986 | 369 | | 1985 | 352 | | 1984 | 332 | | 1983 | 317 | | 1982 | 312 | | 1981 | 313 | | 1980 | 313 | | 1979 | 299 | | 1978 | 293 | | 1977 | 274 | | 1976 | 266 | | 1975 | 252 | | 1974 | 235 | | 1973 | 216 | | 1972 | 193 | | 1971 | 178 | | 1970 | 165 | | 1969 | 175 | | 1968 | 187 | | 1967 | 187 | | 1966 | 198 | | 1965 | 210 | | 1964 | 218 | | 1963 | 233 | | 1962 | 224 | | 1961 | 240 | | 1960 | 215 |
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