| Year | Value | | 2022 | 10,049 | | 2021 | 10,294 | | 2020 | 10,445 | | 2019 | 10,467 | | 2018 | 10,415 | | 2017 | 10,339 | | 2016 | 10,312 | | 2015 | 10,402 | | 2014 | 10,613 | | 2013 | 10,858 | | 2012 | 11,033 | | 2011 | 11,157 | | 2010 | 11,255 | | 2009 | 11,288 | | 2008 | 11,224 | | 2007 | 11,139 | | 2006 | 11,050 | | 2005 | 10,892 | | 2004 | 10,681 | | 2003 | 10,454 | | 2002 | 10,168 | | 2001 | 9,763 | | 2000 | 9,339 | | 1999 | 8,988 | | 1998 | 8,677 | | 1997 | 8,357 | | 1996 | 8,031 | | 1995 | 7,672 | | 1994 | 7,276 | | 1993 | 6,887 | | 1992 | 6,522 | | 1991 | 6,186 | | 1990 | 5,896 | | 1989 | 5,629 | | 1988 | 5,401 | | 1987 | 5,249 | | 1986 | 5,168 | | 1985 | 5,139 | | 1984 | 5,160 | | 1983 | 5,225 | | 1982 | 5,310 | | 1981 | 5,418 | | 1980 | 5,554 | | 1979 | 5,686 | | 1978 | 5,796 | | 1977 | 5,876 | | 1976 | 5,914 | | 1975 | 5,906 | | 1974 | 5,862 | | 1973 | 5,791 | | 1972 | 5,711 | | 1971 | 5,662 | | 1970 | 5,665 | | 1969 | 5,719 | | 1968 | 5,817 | | 1967 | 5,951 | | 1966 | 6,096 | | 1965 | 6,236 | | 1964 | 6,379 | | 1963 | 6,533 | | 1962 | 6,673 | | 1961 | 6,759 | | 1960 | 6,770 |
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