| Year | Value | | 2022 | 4,774 | | 2021 | 4,602 | | 2020 | 4,436 | | 2019 | 4,327 | | 2018 | 4,313 | | 2017 | 4,360 | | 2016 | 4,405 | | 2015 | 4,443 | | 2014 | 4,477 | | 2013 | 4,463 | | 2012 | 4,399 | | 2011 | 4,395 | | 2010 | 4,491 | | 2009 | 4,613 | | 2008 | 4,727 | | 2007 | 4,808 | | 2006 | 4,843 | | 2005 | 4,858 | | 2004 | 4,874 | | 2003 | 4,893 | | 2002 | 4,898 | | 2001 | 4,872 | | 2000 | 4,826 | | 1999 | 4,768 | | 1998 | 4,710 | | 1997 | 4,676 | | 1996 | 4,713 | | 1995 | 4,834 | | 1994 | 4,996 | | 1993 | 5,166 | | 1992 | 5,323 | | 1991 | 5,429 | | 1990 | 5,446 | | 1989 | 5,358 | | 1988 | 5,169 | | 1987 | 4,901 | | 1986 | 4,658 | | 1985 | 4,521 | | 1984 | 4,462 | | 1983 | 4,450 | | 1982 | 4,452 | | 1981 | 4,440 | | 1980 | 4,403 | | 1979 | 4,338 | | 1978 | 4,242 | | 1977 | 4,118 | | 1976 | 3,990 | | 1975 | 3,875 | | 1974 | 3,769 | | 1973 | 3,663 | | 1972 | 3,559 | | 1971 | 3,481 | | 1970 | 3,437 | | 1969 | 3,405 | | 1968 | 3,384 | | 1967 | 3,372 | | 1966 | 3,326 | | 1965 | 3,245 | | 1964 | 3,171 | | 1963 | 3,108 | | 1962 | 3,050 | | 1961 | 2,994 | | 1960 | 2,935 |
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