| Year | Value | | 2022 | 6,643 | | 2021 | 6,610 | | 2020 | 6,611 | | 2019 | 6,693 | | 2018 | 6,835 | | 2017 | 6,966 | | 2016 | 7,046 | | 2015 | 7,041 | | 2014 | 6,949 | | 2013 | 6,786 | | 2012 | 6,588 | | 2011 | 6,396 | | 2010 | 6,195 | | 2009 | 5,961 | | 2008 | 5,701 | | 2007 | 5,413 | | 2006 | 5,118 | | 2005 | 4,840 | | 2004 | 4,589 | | 2003 | 4,364 | | 2002 | 4,162 | | 2001 | 4,028 | | 2000 | 4,007 | | 1999 | 4,019 | | 1998 | 3,989 | | 1997 | 3,929 | | 1996 | 3,839 | | 1995 | 3,724 | | 1994 | 3,589 | | 1993 | 3,443 | | 1992 | 3,293 | | 1991 | 3,151 | | 1990 | 3,026 | | 1989 | 2,913 | | 1988 | 2,797 | | 1987 | 2,678 | | 1986 | 2,567 | | 1985 | 2,470 | | 1984 | 2,391 | | 1983 | 2,333 | | 1982 | 2,289 | | 1981 | 2,271 | | 1980 | 2,254 | | 1979 | 2,197 | | 1978 | 2,111 | | 1977 | 2,029 | | 1976 | 1,972 | | 1975 | 1,946 | | 1974 | 1,953 | | 1973 | 1,985 | | 1972 | 2,025 | | 1971 | 2,051 | | 1970 | 2,081 | | 1969 | 2,271 | | 1968 | 2,594 | | 1967 | 2,893 | | 1966 | 3,160 | | 1965 | 3,409 | | 1964 | 3,655 | | 1963 | 3,891 | | 1962 | 4,091 | | 1961 | 4,226 | | 1960 | 4,173 |
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