| Year | Value | | 2022 | 3,139 | | 2021 | 3,176 | | 2020 | 3,260 | | 2019 | 3,334 | | 2018 | 3,374 | | 2017 | 3,438 | | 2016 | 3,517 | | 2015 | 3,568 | | 2014 | 3,621 | | 2013 | 3,681 | | 2012 | 3,688 | | 2011 | 3,648 | | 2010 | 3,617 | | 2009 | 3,594 | | 2008 | 3,558 | | 2007 | 3,536 | | 2006 | 3,535 | | 2005 | 3,504 | | 2004 | 3,457 | | 2003 | 3,426 | | 2002 | 3,392 | | 2001 | 3,337 | | 2000 | 3,270 | | 1999 | 3,209 | | 1998 | 3,153 | | 1997 | 3,099 | | 1996 | 3,081 | | 1995 | 3,076 | | 1994 | 3,033 | | 1993 | 2,966 | | 1992 | 2,890 | | 1991 | 2,832 | | 1990 | 2,868 | | 1989 | 3,006 | | 1988 | 3,198 | | 1987 | 3,419 | | 1986 | 3,661 | | 1985 | 3,919 | | 1984 | 4,142 | | 1983 | 4,272 | | 1982 | 4,348 | | 1981 | 4,411 | | 1980 | 4,457 | | 1979 | 4,475 | | 1978 | 4,462 | | 1977 | 4,419 | | 1976 | 4,344 | | 1975 | 4,243 | | 1974 | 4,127 | | 1973 | 4,005 | | 1972 | 3,882 | | 1971 | 3,761 | | 1970 | 3,638 | | 1969 | 3,492 | | 1968 | 3,352 | | 1967 | 3,247 | | 1966 | 3,166 | | 1965 | 3,110 | | 1964 | 3,099 | | 1963 | 3,107 | | 1962 | 3,097 | | 1961 | 3,083 | | 1960 | 3,052 |
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