| Year | Value | | 2022 | 12,795 | | 2021 | 12,665 | | 2020 | 12,439 | | 2019 | 12,164 | | 2018 | 12,080 | | 2017 | 12,125 | | 2016 | 12,209 | | 2015 | 12,225 | | 2014 | 12,105 | | 2013 | 11,831 | | 2012 | 11,469 | | 2011 | 11,151 | | 2010 | 10,979 | | 2009 | 10,950 | | 2008 | 11,038 | | 2007 | 11,243 | | 2006 | 11,508 | | 2005 | 11,793 | | 2004 | 12,105 | | 2003 | 12,450 | | 2002 | 12,807 | | 2001 | 13,168 | | 2000 | 13,539 | | 1999 | 13,929 | | 1998 | 14,330 | | 1997 | 14,701 | | 1996 | 14,990 | | 1995 | 15,153 | | 1994 | 15,173 | | 1993 | 15,035 | | 1992 | 14,780 | | 1991 | 14,399 | | 1990 | 13,944 | | 1989 | 13,543 | | 1988 | 13,259 | | 1987 | 13,070 | | 1986 | 12,875 | | 1985 | 12,611 | | 1984 | 12,283 | | 1983 | 11,869 | | 1982 | 11,281 | | 1981 | 10,612 | | 1980 | 10,024 | | 1979 | 9,499 | | 1978 | 9,014 | | 1977 | 8,591 | | 1976 | 8,199 | | 1975 | 7,811 | | 1974 | 7,415 | | 1973 | 6,995 | | 1972 | 6,541 | | 1971 | 6,043 | | 1970 | 5,683 | | 1969 | 5,503 | | 1968 | 5,369 | | 1967 | 5,256 | | 1966 | 5,111 | | 1965 | 4,907 | | 1964 | 4,640 | | 1963 | 4,308 | | 1962 | 3,913 | | 1961 | 3,479 | | 1960 | 3,029 |
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