| Year | Value | | 2022 | 14,987 | | 2021 | 15,232 | | 2020 | 15,434 | | 2019 | 15,416 | | 2018 | 15,069 | | 2017 | 14,639 | | 2016 | 14,271 | | 2015 | 14,123 | | 2014 | 14,062 | | 2013 | 13,781 | | 2012 | 13,529 | | 2011 | 13,344 | | 2010 | 13,184 | | 2009 | 13,104 | | 2008 | 12,976 | | 2007 | 12,906 | | 2006 | 12,895 | | 2005 | 12,835 | | 2004 | 12,537 | | 2003 | 11,927 | | 2002 | 11,453 | | 2001 | 11,200 | | 2000 | 11,007 | | 1999 | 10,780 | | 1998 | 10,525 | | 1997 | 10,298 | | 1996 | 10,098 | | 1995 | 9,498 | | 1994 | 8,820 | | 1993 | 8,872 | | 1992 | 9,002 | | 1991 | 8,520 | | 1990 | 8,153 | | 1989 | 8,077 | | 1988 | 7,835 | | 1987 | 7,566 | | 1986 | 7,188 | | 1985 | 6,856 | | 1984 | 7,046 | | 1983 | 7,300 | | 1982 | 6,596 | | 1981 | 5,777 | | 1980 | 5,852 | | 1979 | 5,953 | | 1978 | 5,768 | | 1977 | 5,642 | | 1976 | 5,539 | | 1975 | 5,459 | | 1974 | 5,393 | | 1973 | 5,343 | | 1972 | 5,318 | | 1971 | 5,312 | | 1970 | 5,304 | | 1969 | 5,292 | | 1968 | 5,279 | | 1967 | 5,263 | | 1966 | 5,248 | | 1965 | 5,220 | | 1964 | 5,169 | | 1963 | 5,087 | | 1962 | 4,976 | | 1961 | 4,857 | | 1960 | 4,749 |
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