| Year | Value | | 2022 | 13,611 | | 2021 | 13,337 | | 2020 | 13,191 | | 2019 | 13,181 | | 2018 | 13,322 | | 2017 | 13,624 | | 2016 | 14,082 | | 2015 | 14,644 | | 2014 | 15,044 | | 2013 | 15,269 | | 2012 | 15,508 | | 2011 | 15,772 | | 2010 | 15,708 | | 2009 | 14,803 | | 2008 | 13,386 | | 2007 | 12,072 | | 2006 | 11,080 | | 2005 | 10,449 | | 2004 | 10,104 | | 2003 | 9,773 | | 2002 | 9,213 | | 2001 | 8,509 | | 2000 | 7,862 | | 1999 | 7,411 | | 1998 | 7,161 | | 1997 | 7,034 | | 1996 | 6,950 | | 1995 | 6,844 | | 1994 | 6,679 | | 1993 | 6,458 | | 1992 | 6,207 | | 1991 | 5,945 | | 1990 | 5,830 | | 1989 | 5,887 | | 1988 | 5,962 | | 1987 | 6,031 | | 1986 | 6,102 | | 1985 | 6,172 | | 1984 | 6,237 | | 1983 | 6,288 | | 1982 | 6,312 | | 1981 | 6,284 | | 1980 | 6,179 | | 1979 | 6,038 | | 1978 | 5,896 | | 1977 | 5,730 | | 1976 | 5,572 | | 1975 | 5,463 | | 1974 | 5,311 | | 1973 | 5,074 | | 1972 | 4,855 | | 1971 | 4,717 | | 1970 | 4,686 | | 1969 | 4,760 | | 1968 | 4,952 | | 1967 | 5,217 | | 1966 | 5,447 | | 1965 | 5,564 | | 1964 | 5,572 | | 1963 | 5,481 | | 1962 | 5,294 | | 1961 | 5,053 | | 1960 | 4,800 |
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