| Year | Value | | 2022 | 3,915 | | 2021 | 3,259 | | 2020 | 3,252 | | 2019 | 3,273 | | 2018 | 3,284 | | 2017 | 3,246 | | 2016 | 3,237 | | 2015 | 3,318 | | 2014 | 3,371 | | 2013 | 3,456 | | 2012 | 3,560 | | 2011 | 3,634 | | 2010 | 3,788 | | 2009 | 3,736 | | 2008 | 3,732 | | 2007 | 3,648 | | 2006 | 3,632 | | 2005 | 3,496 | | 2004 | 3,403 | | 2003 | 3,374 | | 2002 | 3,388 | | 2001 | 3,298 | | 2000 | 3,345 | | 1999 | 3,365 | | 1998 | 3,350 | | 1997 | 3,320 | | 1996 | 3,282 | | 1995 | 3,213 | | 1994 | 3,124 | | 1993 | 2,981 | | 1992 | 2,840 | | 1991 | 2,731 | | 1990 | 2,582 | | 1989 | 2,439 | | 1988 | 2,288 | | 1987 | 2,135 | | 1986 | 1,912 | | 1985 | 1,792 | | 1984 | 1,689 | | 1983 | 1,605 | | 1982 | 1,549 | | 1981 | 1,503 | | 1980 | 1,464 | | 1979 | 1,444 | | 1978 | 1,440 | | 1977 | 1,442 | | 1976 | 1,419 | | 1975 | 1,403 | | 1974 | 1,394 | | 1973 | 1,399 | | 1972 | 1,408 | | 1971 | 1,411 | | 1970 | 1,441 | | 1969 | 1,469 | | 1968 | 1,485 | | 1967 | 1,494 | | 1966 | 1,491 | | 1965 | 1,477 | | 1964 | 1,457 | | 1963 | 1,433 | | 1962 | 1,402 | | 1961 | 1,368 | | 1960 | 1,332 |
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