| Year | Value | | 2022 | 3,703 | | 2021 | 3,678 | | 2020 | 3,666 | | 2019 | 3,669 | | 2018 | 3,664 | | 2017 | 3,676 | | 2016 | 3,710 | | 2015 | 3,706 | | 2014 | 3,673 | | 2013 | 3,648 | | 2012 | 3,611 | | 2011 | 3,547 | | 2010 | 3,466 | | 2009 | 3,396 | | 2008 | 3,336 | | 2007 | 3,285 | | 2006 | 3,280 | | 2005 | 3,309 | | 2004 | 3,330 | | 2003 | 3,345 | | 2002 | 3,364 | | 2001 | 3,396 | | 2000 | 3,437 | | 1999 | 3,479 | | 1998 | 3,521 | | 1997 | 3,541 | | 1996 | 3,509 | | 1995 | 3,451 | | 1994 | 3,386 | | 1993 | 3,302 | | 1992 | 3,202 | | 1991 | 3,118 | | 1990 | 3,143 | | 1989 | 3,244 | | 1988 | 3,319 | | 1987 | 3,356 | | 1986 | 3,337 | | 1985 | 3,258 | | 1984 | 3,124 | | 1983 | 2,950 | | 1982 | 2,762 | | 1981 | 2,583 | | 1980 | 2,427 | | 1979 | 2,304 | | 1978 | 2,216 | | 1977 | 2,155 | | 1976 | 2,107 | | 1975 | 2,074 | | 1974 | 2,044 | | 1973 | 2,011 | | 1972 | 1,976 | | 1971 | 1,935 | | 1970 | 1,879 | | 1969 | 1,865 | | 1968 | 1,914 | | 1967 | 1,976 | | 1966 | 2,040 | | 1965 | 2,094 | | 1964 | 2,128 | | 1963 | 2,128 | | 1962 | 2,102 | | 1961 | 2,068 | | 1960 | 2,008 |
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