| Year | Value | | 2022 | 3,215 | | 2021 | 3,213 | | 2020 | 3,213 | | 2019 | 3,187 | | 2018 | 3,116 | | 2017 | 3,038 | | 2016 | 2,962 | | 2015 | 2,901 | | 2014 | 2,860 | | 2013 | 2,835 | | 2012 | 2,833 | | 2011 | 2,855 | | 2010 | 2,904 | | 2009 | 2,955 | | 2008 | 3,008 | | 2007 | 3,087 | | 2006 | 3,194 | | 2005 | 3,342 | | 2004 | 3,506 | | 2003 | 3,621 | | 2002 | 3,681 | | 2001 | 3,708 | | 2000 | 3,684 | | 1999 | 3,596 | | 1998 | 3,487 | | 1997 | 3,390 | | 1996 | 3,307 | | 1995 | 3,214 | | 1994 | 3,119 | | 1993 | 3,038 | | 1992 | 2,968 | | 1991 | 3,047 | | 1990 | 3,189 | | 1989 | 3,203 | | 1988 | 3,131 | | 1987 | 3,012 | | 1986 | 2,891 | | 1985 | 2,806 | | 1984 | 2,734 | | 1983 | 2,635 | | 1982 | 2,499 | | 1981 | 2,362 | | 1980 | 2,235 | | 1979 | 2,117 | | 1978 | 2,030 | | 1977 | 1,970 | | 1976 | 1,943 | | 1975 | 1,945 | | 1974 | 1,958 | | 1973 | 1,969 | | 1972 | 1,978 | | 1971 | 1,973 | | 1970 | 1,932 | | 1969 | 1,865 | | 1968 | 1,795 | | 1967 | 1,736 | | 1966 | 1,694 | | 1965 | 1,673 | | 1964 | 1,652 | | 1963 | 1,621 | | 1962 | 1,586 | | 1961 | 1,552 | | 1960 | 1,514 |
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