| Year | Value | | 2022 | 25,421 | | 2021 | 23,849 | | 2020 | 22,101 | | 2019 | 20,605 | | 2018 | 19,394 | | 2017 | 18,288 | | 2016 | 17,290 | | 2015 | 16,376 | | 2014 | 15,475 | | 2013 | 14,741 | | 2012 | 14,334 | | 2011 | 14,157 | | 2010 | 14,026 | | 2009 | 13,843 | | 2008 | 13,595 | | 2007 | 13,208 | | 2006 | 12,696 | | 2005 | 12,205 | | 2004 | 11,812 | | 2003 | 11,573 | | 2002 | 11,556 | | 2001 | 11,767 | | 2000 | 12,068 | | 1999 | 12,264 | | 1998 | 12,212 | | 1997 | 11,961 | | 1996 | 11,484 | | 1995 | 10,864 | | 1994 | 10,186 | | 1993 | 9,533 | | 1992 | 9,059 | | 1991 | 8,687 | | 1990 | 8,433 | | 1989 | 8,375 | | 1988 | 8,407 | | 1987 | 8,377 | | 1986 | 8,257 | | 1985 | 8,085 | | 1984 | 7,818 | | 1983 | 7,482 | | 1982 | 7,216 | | 1981 | 6,973 | | 1980 | 6,703 | | 1979 | 6,433 | | 1978 | 6,189 | | 1977 | 5,999 | | 1976 | 5,825 | | 1975 | 5,678 | | 1974 | 5,536 | | 1973 | 5,386 | | 1972 | 5,231 | | 1971 | 5,080 | | 1970 | 4,934 | | 1969 | 4,795 | | 1968 | 4,664 | | 1967 | 4,541 | | 1966 | 4,425 | | 1965 | 4,318 | | 1964 | 4,215 | | 1963 | 4,099 | | 1962 | 3,936 | | 1961 | 3,718 | | 1960 | 3,595 |
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