| Year | Value | | 2022 | 3,864 | | 2021 | 3,144 | | 2020 | 3,082 | | 2019 | 3,048 | | 2018 | 3,038 | | 2017 | 3,038 | | 2016 | 3,115 | | 2015 | 3,238 | | 2014 | 3,336 | | 2013 | 3,467 | | 2012 | 3,538 | | 2011 | 3,554 | | 2010 | 3,643 | | 2009 | 3,514 | | 2008 | 3,479 | | 2007 | 3,426 | | 2006 | 3,440 | | 2005 | 3,398 | | 2004 | 3,435 | | 2003 | 3,490 | | 2002 | 3,527 | | 2001 | 3,463 | | 2000 | 3,611 | | 1999 | 3,735 | | 1998 | 3,819 | | 1997 | 3,877 | | 1996 | 3,839 | | 1995 | 3,759 | | 1994 | 3,732 | | 1993 | 3,666 | | 1992 | 3,643 | | 1991 | 3,700 | | 1990 | 3,659 | | 1989 | 3,613 | | 1988 | 3,601 | | 1987 | 3,630 | | 1986 | 3,550 | | 1985 | 3,618 | | 1984 | 3,683 | | 1983 | 3,744 | | 1982 | 3,810 | | 1981 | 3,832 | | 1980 | 3,810 | | 1979 | 3,771 | | 1978 | 3,706 | | 1977 | 3,591 | | 1976 | 3,387 | | 1975 | 3,196 | | 1974 | 2,992 | | 1973 | 2,795 | | 1972 | 2,614 | | 1971 | 2,427 | | 1970 | 2,271 | | 1969 | 2,136 | | 1968 | 2,026 | | 1967 | 1,948 | | 1966 | 1,895 | | 1965 | 1,859 | | 1964 | 1,832 | | 1963 | 1,810 | | 1962 | 1,793 | | 1961 | 1,777 | | 1960 | 1,759 |
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