| Year | Value | | 2022 | 24,527 | | 2021 | 24,946 | | 2020 | 24,911 | | 2019 | 24,474 | | 2018 | 23,566 | | 2017 | 22,294 | | 2016 | 20,782 | | 2015 | 19,136 | | 2014 | 17,423 | | 2013 | 15,946 | | 2012 | 14,793 | | 2011 | 13,765 | | 2010 | 12,885 | | 2009 | 12,200 | | 2008 | 11,689 | | 2007 | 11,297 | | 2006 | 10,997 | | 2005 | 10,751 | | 2004 | 10,526 | | 2003 | 10,299 | | 2002 | 10,060 | | 2001 | 9,796 | | 2000 | 9,508 | | 1999 | 9,225 | | 1998 | 8,958 | | 1997 | 8,697 | | 1996 | 8,437 | | 1995 | 8,163 | | 1994 | 7,842 | | 1993 | 7,456 | | 1992 | 7,032 | | 1991 | 6,610 | | 1990 | 6,220 | | 1989 | 5,852 | | 1988 | 5,461 | | 1987 | 5,056 | | 1986 | 4,677 | | 1985 | 4,359 | | 1984 | 4,166 | | 1983 | 4,086 | | 1982 | 4,047 | | 1981 | 4,031 | | 1980 | 4,022 | | 1979 | 4,017 | | 1978 | 4,011 | | 1977 | 3,962 | | 1976 | 3,890 | | 1975 | 3,838 | | 1974 | 3,802 | | 1973 | 3,785 | | 1972 | 3,782 | | 1971 | 3,785 | | 1970 | 3,787 | | 1969 | 3,785 | | 1968 | 3,777 | | 1967 | 3,747 | | 1966 | 3,652 | | 1965 | 3,477 | | 1964 | 3,307 | | 1963 | 3,167 | | 1962 | 3,023 | | 1961 | 2,886 | | 1960 | 2,767 |
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