| Year | Value | | 2022 | 4,604 | | 2021 | 3,899 | | 2020 | 3,931 | | 2019 | 3,930 | | 2018 | 3,908 | | 2017 | 3,895 | | 2016 | 3,888 | | 2015 | 3,859 | | 2014 | 3,818 | | 2013 | 3,833 | | 2012 | 3,795 | | 2011 | 3,744 | | 2010 | 3,856 | | 2009 | 3,749 | | 2008 | 3,688 | | 2007 | 3,575 | | 2006 | 3,541 | | 2005 | 3,459 | | 2004 | 3,452 | | 2003 | 3,488 | | 2002 | 3,557 | | 2001 | 3,562 | | 2000 | 3,724 | | 1999 | 3,863 | | 1998 | 3,969 | | 1997 | 3,909 | | 1996 | 3,849 | | 1995 | 3,870 | | 1994 | 3,834 | | 1993 | 3,750 | | 1992 | 3,728 | | 1991 | 3,772 | | 1990 | 3,791 | | 1989 | 3,856 | | 1988 | 3,907 | | 1987 | 3,912 | | 1986 | 3,775 | | 1985 | 3,844 | | 1984 | 3,897 | | 1983 | 3,961 | | 1982 | 4,057 | | 1981 | 4,063 | | 1980 | 4,046 | | 1979 | 4,084 | | 1978 | 4,116 | | 1977 | 4,171 | | 1976 | 4,186 | | 1975 | 4,157 | | 1974 | 4,095 | | 1973 | 4,084 | | 1972 | 4,130 | | 1971 | 4,163 | | 1970 | 4,192 | | 1969 | 4,186 | | 1968 | 4,152 | | 1967 | 4,096 | | 1966 | 4,020 | | 1965 | 3,919 | | 1964 | 3,790 | | 1963 | 3,642 | | 1962 | 3,500 | | 1961 | 3,364 | | 1960 | 3,232 |
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