| Year | Value | | 2022 | 5,255 | | 2021 | 4,339 | | 2020 | 4,354 | | 2019 | 4,366 | | 2018 | 4,393 | | 2017 | 4,441 | | 2016 | 4,409 | | 2015 | 4,343 | | 2014 | 4,246 | | 2013 | 4,118 | | 2012 | 3,971 | | 2011 | 3,889 | | 2010 | 3,892 | | 2009 | 3,678 | | 2008 | 3,622 | | 2007 | 3,535 | | 2006 | 3,511 | | 2005 | 3,431 | | 2004 | 3,420 | | 2003 | 3,452 | | 2002 | 3,517 | | 2001 | 3,440 | | 2000 | 3,478 | | 1999 | 3,467 | | 1998 | 3,377 | | 1997 | 3,142 | | 1996 | 2,937 | | 1995 | 2,844 | | 1994 | 2,705 | | 1993 | 2,498 | | 1992 | 2,298 | | 1991 | 2,154 | | 1990 | 2,017 | | 1989 | 1,915 | | 1988 | 1,823 | | 1987 | 1,753 | | 1986 | 1,638 | | 1985 | 1,594 | | 1984 | 1,554 | | 1983 | 1,522 | | 1982 | 1,502 | | 1981 | 1,473 | | 1980 | 1,440 | | 1979 | 1,420 | | 1978 | 1,409 | | 1977 | 1,410 | | 1976 | 1,393 | | 1975 | 1,384 | | 1974 | 1,382 | | 1973 | 1,388 | | 1972 | 1,392 | | 1971 | 1,383 | | 1970 | 1,384 | | 1969 | 1,377 | | 1968 | 1,364 | | 1967 | 1,346 | | 1966 | 1,321 | | 1965 | 1,295 | | 1964 | 1,267 | | 1963 | 1,238 | | 1962 | 1,211 | | 1961 | 1,182 | | 1960 | 1,149 |
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