| Year | Value | | 2022 | 5,512 | | 2021 | 5,568 | | 2020 | 5,527 | | 2019 | 5,400 | | 2018 | 5,179 | | 2017 | 4,982 | | 2016 | 4,924 | | 2015 | 4,923 | | 2014 | 4,939 | | 2013 | 4,945 | | 2012 | 4,931 | | 2011 | 4,912 | | 2010 | 4,847 | | 2009 | 4,774 | | 2008 | 4,727 | | 2007 | 4,670 | | 2006 | 4,642 | | 2005 | 4,670 | | 2004 | 4,692 | | 2003 | 4,695 | | 2002 | 4,716 | | 2001 | 4,702 | | 2000 | 4,621 | | 1999 | 4,565 | | 1998 | 4,601 | | 1997 | 4,747 | | 1996 | 5,014 | | 1995 | 5,281 | | 1994 | 5,530 | | 1993 | 5,850 | | 1992 | 6,241 | | 1991 | 6,596 | | 1990 | 6,721 | | 1989 | 6,667 | | 1988 | 6,555 | | 1987 | 6,451 | | 1986 | 6,372 | | 1985 | 6,194 | | 1984 | 5,951 | | 1983 | 5,744 | | 1982 | 5,587 | | 1981 | 5,483 | | 1980 | 5,364 | | 1979 | 5,207 | | 1978 | 5,101 | | 1977 | 5,104 | | 1976 | 5,185 | | 1975 | 5,197 | | 1974 | 5,146 | | 1973 | 5,121 | | 1972 | 5,146 | | 1971 | 5,214 | | 1970 | 5,156 | | 1969 | 4,914 | | 1968 | 4,597 | | 1967 | 4,213 | | 1966 | 3,829 | | 1965 | 3,613 | | 1964 | 3,559 | | 1963 | 3,581 | | 1962 | 3,666 | | 1961 | 3,770 | | 1960 | 3,802 |
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