| Year | Value | | 2022 | 25,182 | | 2021 | 24,438 | | 2020 | 23,735 | | 2019 | 22,929 | | 2018 | 21,976 | | 2017 | 20,937 | | 2016 | 19,968 | | 2015 | 19,119 | | 2014 | 18,318 | | 2013 | 17,632 | | 2012 | 17,090 | | 2011 | 16,672 | | 2010 | 16,326 | | 2009 | 15,999 | | 2008 | 15,648 | | 2007 | 15,246 | | 2006 | 14,792 | | 2005 | 14,298 | | 2004 | 13,753 | | 2003 | 13,385 | | 2002 | 13,091 | | 2001 | 12,629 | | 2000 | 12,136 | | 1999 | 11,678 | | 1998 | 11,363 | | 1997 | 11,149 | | 1996 | 10,925 | | 1995 | 10,686 | | 1994 | 10,424 | | 1993 | 10,130 | | 1992 | 9,802 | | 1991 | 9,434 | | 1990 | 9,049 | | 1989 | 8,626 | | 1988 | 8,186 | | 1987 | 7,846 | | 1986 | 7,652 | | 1985 | 7,569 | | 1984 | 7,625 | | 1983 | 7,813 | | 1982 | 8,012 | | 1981 | 8,177 | | 1980 | 8,276 | | 1979 | 8,272 | | 1978 | 8,203 | | 1977 | 8,111 | | 1976 | 8,000 | | 1975 | 7,862 | | 1974 | 7,691 | | 1973 | 7,487 | | 1972 | 7,264 | | 1971 | 7,036 | | 1970 | 6,820 | | 1969 | 6,624 | | 1968 | 6,446 | | 1967 | 6,296 | | 1966 | 6,173 | | 1965 | 6,061 | | 1964 | 5,956 | | 1963 | 5,859 | | 1962 | 5,770 | | 1961 | 5,689 | | 1960 | 5,616 |
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