| Year | Value | | 2022 | 14,286 | | 2021 | 14,213 | | 2020 | 14,196 | | 2019 | 13,984 | | 2018 | 13,389 | | 2017 | 12,612 | | 2016 | 11,981 | | 2015 | 11,573 | | 2014 | 11,265 | | 2013 | 11,094 | | 2012 | 11,082 | | 2011 | 11,254 | | 2010 | 11,558 | | 2009 | 11,902 | | 2008 | 11,876 | | 2007 | 11,404 | | 2006 | 10,954 | | 2005 | 10,611 | | 2004 | 10,325 | | 2003 | 10,302 | | 2002 | 10,518 | | 2001 | 10,577 | | 2000 | 10,334 | | 1999 | 10,113 | | 1998 | 9,917 | | 1997 | 9,692 | | 1996 | 9,767 | | 1995 | 10,109 | | 1994 | 10,443 | | 1993 | 10,726 | | 1992 | 10,932 | | 1991 | 10,879 | | 1990 | 10,794 | | 1989 | 10,802 | | 1988 | 10,642 | | 1987 | 10,411 | | 1986 | 10,323 | | 1985 | 10,281 | | 1984 | 10,105 | | 1983 | 9,877 | | 1982 | 9,594 | | 1981 | 9,316 | | 1980 | 9,055 | | 1979 | 8,818 | | 1978 | 8,678 | | 1977 | 8,578 | | 1976 | 8,377 | | 1975 | 8,098 | | 1974 | 7,816 | | 1973 | 7,502 | | 1972 | 7,214 | | 1971 | 6,937 | | 1970 | 6,667 | | 1969 | 6,433 | | 1968 | 6,122 | | 1967 | 5,771 | | 1966 | 5,596 | | 1965 | 5,546 | | 1964 | 5,562 | | 1963 | 5,639 | | 1962 | 5,752 | | 1961 | 5,804 | | 1960 | 5,879 |
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