| Year | Value | | 2022 | 13,535 | | 2021 | 13,738 | | 2020 | 13,815 | | 2019 | 13,688 | | 2018 | 13,361 | | 2017 | 12,922 | | 2016 | 12,436 | | 2015 | 12,014 | | 2014 | 11,691 | | 2013 | 11,385 | | 2012 | 11,014 | | 2011 | 10,542 | | 2010 | 9,965 | | 2009 | 9,287 | | 2008 | 8,527 | | 2007 | 7,767 | | 2006 | 7,059 | | 2005 | 6,440 | | 2004 | 5,953 | | 2003 | 5,625 | | 2002 | 5,421 | | 2001 | 5,308 | | 2000 | 5,284 | | 1999 | 5,349 | | 1998 | 5,511 | | 1997 | 5,789 | | 1996 | 6,171 | | 1995 | 6,526 | | 1994 | 6,778 | | 1993 | 6,951 | | 1992 | 7,060 | | 1991 | 7,103 | | 1990 | 7,148 | | 1989 | 7,286 | | 1988 | 7,399 | | 1987 | 7,421 | | 1986 | 7,373 | | 1985 | 7,228 | | 1984 | 7,001 | | 1983 | 6,710 | | 1982 | 6,377 | | 1981 | 6,042 | | 1980 | 5,751 | | 1979 | 5,577 | | 1978 | 5,505 | | 1977 | 5,478 | | 1976 | 5,481 | | 1975 | 5,497 | | 1974 | 5,522 | | 1973 | 5,572 | | 1972 | 5,638 | | 1971 | 5,672 | | 1970 | 5,640 | | 1969 | 5,541 | | 1968 | 5,358 | | 1967 | 5,100 | | 1966 | 4,827 | | 1965 | 4,579 | | 1964 | 4,357 | | 1963 | 4,160 | | 1962 | 4,000 | | 1961 | 3,854 | | 1960 | 3,710 |
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