| Year | Value | | 2022 | 6,769 | | 2021 | 6,584 | | 2020 | 6,346 | | 2019 | 6,037 | | 2018 | 5,713 | | 2017 | 5,413 | | 2016 | 5,156 | | 2015 | 4,937 | | 2014 | 4,661 | | 2013 | 4,320 | | 2012 | 4,006 | | 2011 | 3,726 | | 2010 | 3,507 | | 2009 | 3,414 | | 2008 | 3,438 | | 2007 | 3,493 | | 2006 | 3,516 | | 2005 | 3,481 | | 2004 | 3,340 | | 2003 | 3,085 | | 2002 | 2,797 | | 2001 | 2,527 | | 2000 | 2,284 | | 1999 | 2,082 | | 1998 | 1,908 | | 1997 | 1,748 | | 1996 | 1,610 | | 1995 | 1,495 | | 1994 | 1,406 | | 1993 | 1,338 | | 1992 | 1,295 | | 1991 | 1,268 | | 1990 | 1,252 | | 1989 | 1,226 | | 1988 | 1,187 | | 1987 | 1,138 | | 1986 | 1,081 | | 1985 | 1,031 | | 1984 | 998 | | 1983 | 991 | | 1982 | 1,013 | | 1981 | 1,060 | | 1980 | 1,090 | | 1979 | 1,084 | | 1978 | 1,059 | | 1977 | 1,013 | | 1976 | 961 | | 1975 | 916 | | 1974 | 873 | | 1973 | 816 | | 1972 | 753 | | 1971 | 706 | | 1970 | 679 | | 1969 | 679 | | 1968 | 709 | | 1967 | 767 | | 1966 | 827 | | 1965 | 871 | | 1964 | 898 | | 1963 | 903 | | 1962 | 886 | | 1961 | 862 | | 1960 | 847 |
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