| Year | Value | | 2022 | 6,052 | | 2021 | 6,323 | | 2020 | 6,634 | | 2019 | 7,338 | | 2018 | 7,077 | | 2017 | 6,164 | | 2016 | 6,078 | | 2015 | 5,795 | | 2014 | 5,363 | | 2013 | 4,858 | | 2012 | 4,345 | | 2011 | 4,027 | | 2010 | 3,997 | | 2009 | 4,127 | | 2008 | 4,293 | | 2007 | 4,386 | | 2006 | 4,365 | | 2005 | 4,231 | | 2004 | 4,022 | | 2003 | 3,811 | | 2002 | 3,570 | | 2001 | 3,403 | | 2000 | 3,458 | | 1999 | 3,641 | | 1998 | 3,872 | | 1997 | 4,080 | | 1996 | 4,227 | | 1995 | 4,387 | | 1994 | 4,611 | | 1993 | 4,875 | | 1992 | 5,180 | | 1991 | 5,559 | | 1990 | 5,969 | | 1989 | 6,386 | | 1988 | 6,816 | | 1987 | 7,216 | | 1986 | 7,538 | | 1985 | 7,760 | | 1984 | 7,892 | | 1983 | 7,963 | | 1982 | 7,950 | | 1981 | 7,835 | | 1980 | 7,692 | | 1979 | 7,513 | | 1978 | 7,337 | | 1977 | 7,184 | | 1976 | 6,985 | | 1975 | 6,789 | | 1974 | 6,587 | | 1973 | 6,381 | | 1972 | 6,260 | | 1971 | 6,108 | | 1970 | 5,921 | | 1969 | 5,771 | | 1968 | 5,603 | | 1967 | 5,417 | | 1966 | 5,246 | | 1965 | 5,081 | | 1964 | 4,909 | | 1963 | 4,762 | | 1962 | 4,642 | | 1961 | 4,553 | | 1960 | 4,543 |
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