| Year | Value | | 2022 | 12,120 | | 2021 | 12,527 | | 2020 | 13,037 | | 2019 | 13,541 | | 2018 | 13,971 | | 2017 | 14,270 | | 2016 | 14,417 | | 2015 | 14,411 | | 2014 | 14,278 | | 2013 | 14,067 | | 2012 | 13,744 | | 2011 | 13,217 | | 2010 | 12,272 | | 2009 | 10,988 | | 2008 | 9,786 | | 2007 | 8,759 | | 2006 | 7,779 | | 2005 | 6,825 | | 2004 | 6,088 | | 2003 | 5,754 | | 2002 | 5,702 | | 2001 | 5,743 | | 2000 | 5,786 | | 1999 | 5,771 | | 1998 | 5,659 | | 1997 | 5,457 | | 1996 | 5,212 | | 1995 | 4,952 | | 1994 | 4,694 | | 1993 | 4,445 | | 1992 | 4,208 | | 1991 | 3,980 | | 1990 | 3,902 | | 1989 | 3,997 | | 1988 | 4,108 | | 1987 | 4,201 | | 1986 | 4,261 | | 1985 | 4,263 | | 1984 | 4,195 | | 1983 | 4,057 | | 1982 | 3,857 | | 1981 | 3,605 | | 1980 | 3,401 | | 1979 | 3,325 | | 1978 | 3,323 | | 1977 | 3,346 | | 1976 | 3,421 | | 1975 | 3,583 | | 1974 | 3,739 | | 1973 | 3,885 | | 1972 | 4,079 | | 1971 | 4,247 | | 1970 | 4,324 | | 1969 | 4,315 | | 1968 | 4,229 | | 1967 | 4,069 | | 1966 | 3,868 | | 1965 | 3,664 | | 1964 | 3,447 | | 1963 | 3,191 | | 1962 | 2,935 | | 1961 | 2,746 | | 1960 | 2,660 |
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