| Year | Value | | 2022 | 3,822 | | 2021 | 3,177 | | 2020 | 3,263 | | 2019 | 3,357 | | 2018 | 3,459 | | 2017 | 3,588 | | 2016 | 3,643 | | 2015 | 3,640 | | 2014 | 3,600 | | 2013 | 3,547 | | 2012 | 3,480 | | 2011 | 3,454 | | 2010 | 3,489 | | 2009 | 3,320 | | 2008 | 3,271 | | 2007 | 3,188 | | 2006 | 3,201 | | 2005 | 3,197 | | 2004 | 3,239 | | 2003 | 3,307 | | 2002 | 3,392 | | 2001 | 3,297 | | 2000 | 3,271 | | 1999 | 3,189 | | 1998 | 3,032 | | 1997 | 2,875 | | 1996 | 2,744 | | 1995 | 2,582 | | 1994 | 2,412 | | 1993 | 2,212 | | 1992 | 2,021 | | 1991 | 1,868 | | 1990 | 1,726 | | 1989 | 1,619 | | 1988 | 1,523 | | 1987 | 1,452 | | 1986 | 1,351 | | 1985 | 1,314 | | 1984 | 1,293 | | 1983 | 1,289 | | 1982 | 1,305 | | 1981 | 1,315 | | 1980 | 1,321 | | 1979 | 1,337 | | 1978 | 1,360 | | 1977 | 1,385 | | 1976 | 1,389 | | 1975 | 1,400 | | 1974 | 1,404 | | 1973 | 1,403 | | 1972 | 1,402 | | 1971 | 1,390 | | 1970 | 1,384 | | 1969 | 1,377 | | 1968 | 1,366 | | 1967 | 1,348 | | 1966 | 1,327 | | 1965 | 1,303 | | 1964 | 1,279 | | 1963 | 1,259 | | 1962 | 1,239 | | 1961 | 1,216 | | 1960 | 1,187 |
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