| Year | Value | | 2022 | 8,714 | | 2021 | 8,736 | | 2020 | 8,878 | | 2019 | 9,114 | | 2018 | 9,308 | | 2017 | 9,310 | | 2016 | 9,164 | | 2015 | 8,955 | | 2014 | 8,734 | | 2013 | 8,520 | | 2012 | 8,327 | | 2011 | 8,169 | | 2010 | 8,056 | | 2009 | 7,974 | | 2008 | 7,924 | | 2007 | 7,902 | | 2006 | 7,885 | | 2005 | 7,865 | | 2004 | 7,849 | | 2003 | 7,835 | | 2002 | 7,739 | | 2001 | 7,559 | | 2000 | 7,381 | | 1999 | 7,205 | | 1998 | 7,036 | | 1997 | 6,872 | | 1996 | 6,693 | | 1995 | 6,483 | | 1994 | 6,274 | | 1993 | 6,066 | | 1992 | 5,798 | | 1991 | 5,484 | | 1990 | 5,205 | | 1989 | 4,982 | | 1988 | 4,816 | | 1987 | 4,697 | | 1986 | 4,594 | | 1985 | 4,495 | | 1984 | 4,401 | | 1983 | 4,265 | | 1982 | 4,091 | | 1981 | 3,925 | | 1980 | 3,756 | | 1979 | 3,583 | | 1978 | 3,411 | | 1977 | 3,242 | | 1976 | 3,074 | | 1975 | 2,909 | | 1974 | 2,748 | | 1973 | 2,628 | | 1972 | 2,548 | | 1971 | 2,471 | | 1970 | 2,398 | | 1969 | 2,330 | | 1968 | 2,263 | | 1967 | 2,198 | | 1966 | 2,137 | | 1965 | 2,076 | | 1964 | 2,018 | | 1963 | 1,960 | | 1962 | 1,905 | | 1961 | 1,852 | | 1960 | 1,799 |
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