| Year | Value | | 2023 | 6,280 | | 2022 | 6,263 | | 2021 | 6,326 | | 2020 | 6,427 | | 2019 | 6,513 | | 2018 | 6,499 | | 2017 | 6,367 | | 2016 | 6,185 | | 2015 | 5,944 | | 2014 | 5,640 | | 2013 | 5,369 | | 2012 | 5,151 | | 2011 | 4,916 | | 2010 | 4,678 | | 2009 | 4,450 | | 2008 | 4,235 | | 2007 | 4,041 | | 2006 | 3,866 | | 2005 | 3,707 | | 2004 | 3,561 | | 2003 | 3,421 | | 2002 | 3,281 | | 2001 | 3,140 | | 2000 | 3,000 | | 1999 | 2,865 | | 1998 | 2,741 | | 1997 | 2,629 | | 1996 | 2,532 | | 1995 | 2,448 | | 1994 | 2,376 | | 1993 | 2,314 | | 1992 | 2,257 | | 1991 | 2,202 | | 1990 | 2,149 | | 1989 | 2,092 | | 1988 | 2,031 | | 1987 | 1,967 | | 1986 | 1,898 | | 1985 | 1,825 | | 1984 | 1,748 | | 1983 | 1,664 | | 1982 | 1,577 | | 1981 | 1,488 | | 1980 | 1,407 | | 1979 | 1,345 | | 1978 | 1,305 | | 1977 | 1,289 | | 1976 | 1,291 | | 1975 | 1,293 | | 1974 | 1,282 |
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