| Year | Value | | 2022 | 4,502 | | 2021 | 4,426 | | 2020 | 4,423 | | 2019 | 4,506 | | 2018 | 4,612 | | 2017 | 4,729 | | 2016 | 4,859 | | 2015 | 4,942 | | 2014 | 4,987 | | 2013 | 5,065 | | 2012 | 5,181 | | 2011 | 5,342 | | 2010 | 5,567 | | 2009 | 5,832 | | 2008 | 6,087 | | 2007 | 6,298 | | 2006 | 6,434 | | 2005 | 6,470 | | 2004 | 6,403 | | 2003 | 6,248 | | 2002 | 6,074 | | 2001 | 5,880 | | 2000 | 5,613 | | 1999 | 5,328 | | 1998 | 5,082 | | 1997 | 4,919 | | 1996 | 4,883 | | 1995 | 4,919 | | 1994 | 5,007 | | 1993 | 5,136 | | 1992 | 5,221 | | 1991 | 5,215 | | 1990 | 5,188 | | 1989 | 5,228 | | 1988 | 5,342 | | 1987 | 5,525 | | 1986 | 5,741 | | 1985 | 5,918 | | 1984 | 6,029 | | 1983 | 6,092 | | 1982 | 6,103 | | 1981 | 6,090 | | 1980 | 6,166 | | 1979 | 6,291 | | 1978 | 6,369 | | 1977 | 6,427 | | 1976 | 6,457 | | 1975 | 6,449 | | 1974 | 6,389 | | 1973 | 6,272 | | 1972 | 6,098 | | 1971 | 5,877 | | 1970 | 5,619 | | 1969 | 5,352 | | 1968 | 5,115 | | 1967 | 4,925 | | 1966 | 4,768 | | 1965 | 4,628 | | 1964 | 4,497 | | 1963 | 4,375 | | 1962 | 4,267 | | 1961 | 4,177 | | 1960 | 4,107 |
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