| Year | Value | | 2022 | 11,810 | | 2021 | 11,916 | | 2020 | 12,044 | | 2019 | 12,168 | | 2018 | 12,174 | | 2017 | 12,131 | | 2016 | 12,095 | | 2015 | 11,885 | | 2014 | 11,483 | | 2013 | 10,999 | | 2012 | 10,570 | | 2011 | 10,236 | | 2010 | 10,027 | | 2009 | 10,030 | | 2008 | 10,200 | | 2007 | 10,366 | | 2006 | 10,511 | | 2005 | 10,711 | | 2004 | 10,917 | | 2003 | 11,094 | | 2002 | 11,221 | | 2001 | 11,289 | | 2000 | 11,299 | | 1999 | 11,242 | | 1998 | 11,115 | | 1997 | 10,914 | | 1996 | 10,666 | | 1995 | 10,386 | | 1994 | 10,067 | | 1993 | 9,737 | | 1992 | 9,411 | | 1991 | 9,089 | | 1990 | 8,759 | | 1989 | 8,416 | | 1988 | 8,050 | | 1987 | 7,670 | | 1986 | 7,311 | | 1985 | 6,991 | | 1984 | 6,727 | | 1983 | 6,572 | | 1982 | 6,408 | | 1981 | 6,186 | | 1980 | 6,002 | | 1979 | 5,836 | | 1978 | 5,669 | | 1977 | 5,484 | | 1976 | 5,283 | | 1975 | 5,073 | | 1974 | 4,852 | | 1973 | 4,633 | | 1972 | 4,433 | | 1971 | 4,246 | | 1970 | 4,072 | | 1969 | 3,921 | | 1968 | 3,779 | | 1967 | 3,634 | | 1966 | 3,476 | | 1965 | 3,305 | | 1964 | 3,126 | | 1963 | 2,975 | | 1962 | 2,864 | | 1961 | 2,779 | | 1960 | 2,713 |
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