| Year | Value | | 2022 | 4,149 | | 2021 | 4,135 | | 2020 | 4,123 | | 2019 | 4,038 | | 2018 | 4,120 | | 2017 | 4,276 | | 2016 | 4,223 | | 2015 | 4,172 | | 2014 | 4,134 | | 2013 | 4,105 | | 2012 | 4,082 | | 2011 | 4,024 | | 2010 | 3,852 | | 2009 | 3,641 | | 2008 | 3,455 | | 2007 | 3,255 | | 2006 | 3,050 | | 2005 | 2,848 | | 2004 | 2,676 | | 2003 | 2,555 | | 2002 | 2,459 | | 2001 | 2,444 | | 2000 | 2,526 | | 1999 | 2,609 | | 1998 | 2,675 | | 1997 | 2,677 | | 1996 | 2,598 | | 1995 | 2,496 | | 1994 | 2,399 | | 1993 | 2,304 | | 1992 | 2,220 | | 1991 | 2,158 | | 1990 | 2,107 | | 1989 | 2,069 | | 1988 | 2,046 | | 1987 | 2,028 | | 1986 | 2,004 | | 1985 | 1,969 | | 1984 | 1,925 | | 1983 | 1,878 | | 1982 | 1,819 | | 1981 | 1,750 | | 1980 | 1,692 | | 1979 | 1,643 | | 1978 | 1,618 | | 1977 | 1,626 | | 1976 | 1,653 | | 1975 | 1,705 | | 1974 | 1,767 | | 1973 | 1,820 | | 1972 | 1,900 | | 1971 | 1,962 | | 1970 | 1,972 | | 1969 | 1,955 | | 1968 | 1,905 | | 1967 | 1,827 | | 1966 | 1,736 | | 1965 | 1,637 | | 1964 | 1,527 | | 1963 | 1,423 | | 1962 | 1,332 | | 1961 | 1,252 | | 1960 | 1,208 |
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