| Year | Value | | 2022 | 6,147 | | 2021 | 6,092 | | 2020 | 6,027 | | 2019 | 5,931 | | 2018 | 5,748 | | 2017 | 5,572 | | 2016 | 5,432 | | 2015 | 5,259 | | 2014 | 5,158 | | 2013 | 5,135 | | 2012 | 5,126 | | 2011 | 5,211 | | 2010 | 5,313 | | 2009 | 5,317 | | 2008 | 5,261 | | 2007 | 5,202 | | 2006 | 5,130 | | 2005 | 5,048 | | 2004 | 5,009 | | 2003 | 5,013 | | 2002 | 5,079 | | 2001 | 5,257 | | 2000 | 5,507 | | 1999 | 5,769 | | 1998 | 6,025 | | 1997 | 6,254 | | 1996 | 6,445 | | 1995 | 6,614 | | 1994 | 6,753 | | 1993 | 6,864 | | 1992 | 6,890 | | 1991 | 6,781 | | 1990 | 6,570 | | 1989 | 6,341 | | 1988 | 6,170 | | 1987 | 6,016 | | 1986 | 5,852 | | 1985 | 5,674 | | 1984 | 5,483 | | 1983 | 5,317 | | 1982 | 5,203 | | 1981 | 5,120 | | 1980 | 5,118 | | 1979 | 5,254 | | 1978 | 5,462 | | 1977 | 5,665 | | 1976 | 5,724 | | 1975 | 5,529 | | 1974 | 5,196 | | 1973 | 4,871 | | 1972 | 4,528 | | 1971 | 4,156 | | 1970 | 3,899 | | 1969 | 3,774 | | 1968 | 3,716 | | 1967 | 3,737 | | 1966 | 3,807 | | 1965 | 3,837 | | 1964 | 3,803 | | 1963 | 3,731 | | 1962 | 3,643 | | 1961 | 3,543 | | 1960 | 3,432 |
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