| Year | Value | | 2022 | 4,721 | | 2021 | 4,671 | | 2020 | 4,603 | | 2019 | 4,653 | | 2018 | 4,328 | | 2017 | 3,820 | | 2016 | 3,790 | | 2015 | 3,800 | | 2014 | 3,863 | | 2013 | 3,962 | | 2012 | 4,082 | | 2011 | 4,203 | | 2010 | 4,217 | | 2009 | 4,176 | | 2008 | 4,191 | | 2007 | 4,242 | | 2006 | 4,333 | | 2005 | 4,442 | | 2004 | 4,552 | | 2003 | 4,674 | | 2002 | 4,750 | | 2001 | 4,896 | | 2000 | 5,199 | | 1999 | 5,495 | | 1998 | 5,731 | | 1997 | 5,815 | | 1996 | 5,722 | | 1995 | 5,568 | | 1994 | 5,418 | | 1993 | 5,266 | | 1992 | 5,112 | | 1991 | 4,998 | | 1990 | 4,913 | | 1989 | 4,854 | | 1988 | 4,830 | | 1987 | 4,811 | | 1986 | 4,769 | | 1985 | 4,699 | | 1984 | 4,603 | | 1983 | 4,495 | | 1982 | 4,357 | | 1981 | 4,200 | | 1980 | 4,073 | | 1979 | 3,969 | | 1978 | 3,904 | | 1977 | 3,888 | | 1976 | 3,877 | | 1975 | 3,885 | | 1974 | 3,894 | | 1973 | 3,888 | | 1972 | 3,939 | | 1971 | 3,940 | | 1970 | 3,852 | | 1969 | 3,778 | | 1968 | 3,713 | | 1967 | 3,664 | | 1966 | 3,645 | | 1965 | 3,635 | | 1964 | 3,613 | | 1963 | 3,586 | | 1962 | 3,561 | | 1961 | 3,555 | | 1960 | 3,584 |
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