| Year | Value | | 2022 | 1,701 | | 2021 | 1,632 | | 2020 | 1,590 | | 2019 | 1,557 | | 2018 | 1,516 | | 2017 | 1,460 | | 2016 | 1,389 | | 2015 | 1,313 | | 2014 | 1,248 | | 2013 | 1,200 | | 2012 | 1,166 | | 2011 | 1,145 | | 2010 | 1,139 | | 2009 | 1,134 | | 2008 | 1,120 | | 2007 | 1,093 | | 2006 | 1,058 | | 2005 | 1,011 | | 2004 | 961 | | 2003 | 921 | | 2002 | 885 | | 2001 | 853 | | 2000 | 823 | | 1999 | 795 | | 1998 | 766 | | 1997 | 733 | | 1996 | 693 | | 1995 | 647 | | 1994 | 605 | | 1993 | 577 | | 1992 | 571 | | 1991 | 578 | | 1990 | 589 | | 1989 | 594 | | 1988 | 592 | | 1987 | 588 | | 1986 | 584 | | 1985 | 577 | | 1984 | 562 | | 1983 | 542 | | 1982 | 514 | | 1981 | 484 | | 1980 | 462 | | 1979 | 445 | | 1978 | 423 | | 1977 | 396 | | 1976 | 363 | | 1975 | 328 | | 1974 | 293 | | 1973 | 261 | | 1972 | 236 | | 1971 | 227 | | 1970 | 231 | | 1969 | 235 | | 1968 | 232 | | 1967 | 223 | | 1966 | 214 | | 1965 | 208 | | 1964 | 202 | | 1963 | 194 | | 1962 | 185 | | 1961 | 175 | | 1960 | 172 |
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