| Year | Value | | 2022 | 25,786 | | 2021 | 24,808 | | 2020 | 23,811 | | 2019 | 22,854 | | 2018 | 21,987 | | 2017 | 21,122 | | 2016 | 20,250 | | 2015 | 19,446 | | 2014 | 18,699 | | 2013 | 18,004 | | 2012 | 17,371 | | 2011 | 16,746 | | 2010 | 16,124 | | 2009 | 15,546 | | 2008 | 15,015 | | 2007 | 14,527 | | 2006 | 14,088 | | 2005 | 13,697 | | 2004 | 13,340 | | 2003 | 13,022 | | 2002 | 12,767 | | 2001 | 12,452 | | 2000 | 12,034 | | 1999 | 11,628 | | 1998 | 11,247 | | 1997 | 10,900 | | 1996 | 10,599 | | 1995 | 10,357 | | 1994 | 10,172 | | 1993 | 10,041 | | 1992 | 9,848 | | 1991 | 9,535 | | 1990 | 9,175 | | 1989 | 8,773 | | 1988 | 8,340 | | 1987 | 7,910 | | 1986 | 7,516 | | 1985 | 7,168 | | 1984 | 6,891 | | 1983 | 6,699 | | 1982 | 6,610 | | 1981 | 6,553 | | 1980 | 6,402 | | 1979 | 6,139 | | 1978 | 5,803 | | 1977 | 5,477 | | 1976 | 5,228 | | 1975 | 5,189 | | 1974 | 5,350 | | 1973 | 5,580 | | 1972 | 5,606 | | 1971 | 5,409 | | 1970 | 5,192 | | 1969 | 4,883 | | 1968 | 4,463 | | 1967 | 3,963 | | 1966 | 3,477 | | 1965 | 3,124 | | 1964 | 2,987 | | 1963 | 3,056 | | 1962 | 3,269 | | 1961 | 3,546 | | 1960 | 3,632 |
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