| Year | Value | | 2022 | 27,300 | | 2021 | 25,833 | | 2020 | 24,325 | | 2019 | 22,807 | | 2018 | 21,372 | | 2017 | 20,044 | | 2016 | 18,855 | | 2015 | 17,764 | | 2014 | 16,755 | | 2013 | 15,854 | | 2012 | 15,057 | | 2011 | 14,349 | | 2010 | 13,750 | | 2009 | 13,263 | | 2008 | 12,890 | | 2007 | 12,612 | | 2006 | 12,385 | | 2005 | 12,178 | | 2004 | 11,965 | | 2003 | 11,781 | | 2002 | 11,619 | | 2001 | 11,480 | | 2000 | 11,377 | | 1999 | 11,276 | | 1998 | 11,122 | | 1997 | 10,937 | | 1996 | 10,732 | | 1995 | 10,499 | | 1994 | 10,284 | | 1993 | 10,083 | | 1992 | 9,890 | | 1991 | 9,681 | | 1990 | 9,464 | | 1989 | 9,258 | | 1988 | 9,065 | | 1987 | 8,872 | | 1986 | 8,673 | | 1985 | 8,497 | | 1984 | 8,355 | | 1983 | 8,249 | | 1982 | 8,166 | | 1981 | 8,127 | | 1980 | 8,130 | | 1979 | 8,112 | | 1978 | 8,066 | | 1977 | 8,019 | | 1976 | 7,947 | | 1975 | 7,824 | | 1974 | 7,656 | | 1973 | 7,457 | | 1972 | 7,239 | | 1971 | 6,971 | | 1970 | 6,643 | | 1969 | 6,227 | | 1968 | 5,779 | | 1967 | 5,397 | | 1966 | 5,071 | | 1965 | 4,785 | | 1964 | 4,501 | | 1963 | 4,176 | | 1962 | 3,823 | | 1961 | 3,505 | | 1960 | 3,328 |
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