| Year | Value | | 2022 | 2,360 | | 2021 | 2,259 | | 2020 | 2,153 | | 2019 | 2,053 | | 2018 | 1,958 | | 2017 | 1,867 | | 2016 | 1,785 | | 2015 | 1,720 | | 2014 | 1,672 | | 2013 | 1,639 | | 2012 | 1,618 | | 2011 | 1,612 | | 2010 | 1,615 | | 2009 | 1,624 | | 2008 | 1,630 | | 2007 | 1,632 | | 2006 | 1,625 | | 2005 | 1,608 | | 2004 | 1,583 | | 2003 | 1,556 | | 2002 | 1,527 | | 2001 | 1,497 | | 2000 | 1,470 | | 1999 | 1,445 | | 1998 | 1,430 | | 1997 | 1,433 | | 1996 | 1,453 | | 1995 | 1,489 | | 1994 | 1,536 | | 1993 | 1,573 | | 1992 | 1,588 | | 1991 | 1,568 | | 1990 | 1,503 | | 1989 | 1,412 | | 1988 | 1,325 | | 1987 | 1,253 | | 1986 | 1,196 | | 1985 | 1,144 | | 1984 | 1,097 | | 1983 | 1,055 | | 1982 | 1,013 | | 1981 | 975 | | 1980 | 952 | | 1979 | 934 | | 1978 | 919 | | 1977 | 907 | | 1976 | 881 | | 1975 | 839 | | 1974 | 798 | | 1973 | 767 | | 1972 | 750 | | 1971 | 740 | | 1970 | 735 | | 1969 | 732 | | 1968 | 732 | | 1967 | 731 | | 1966 | 713 | | 1965 | 680 | | 1964 | 649 | | 1963 | 617 | | 1962 | 585 | | 1961 | 563 | | 1960 | 549 |
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