| Year | Value | | 2022 | 18,160 | | 2021 | 17,662 | | 2020 | 17,260 | | 2019 | 16,538 | | 2018 | 16,020 | | 2017 | 15,399 | | 2016 | 14,638 | | 2015 | 13,827 | | 2014 | 12,995 | | 2013 | 12,159 | | 2012 | 11,352 | | 2011 | 10,666 | | 2010 | 10,001 | | 2009 | 9,278 | | 2008 | 8,578 | | 2007 | 7,981 | | 2006 | 7,568 | | 2005 | 7,327 | | 2004 | 7,174 | | 2003 | 7,114 | | 2002 | 7,126 | | 2001 | 7,118 | | 2000 | 7,099 | | 1999 | 7,077 | | 1998 | 7,062 | | 1997 | 7,053 | | 1996 | 7,024 | | 1995 | 6,955 | | 1994 | 6,839 | | 1993 | 6,741 | | 1992 | 6,683 | | 1991 | 6,620 | | 1990 | 6,556 | | 1989 | 6,489 | | 1988 | 6,422 | | 1987 | 6,348 | | 1986 | 6,253 | | 1985 | 6,129 | | 1984 | 5,953 | | 1983 | 5,740 | | 1982 | 5,531 | | 1981 | 5,334 | | 1980 | 5,149 | | 1979 | 4,976 | | 1978 | 4,811 | | 1977 | 4,655 | | 1976 | 4,506 | | 1975 | 4,363 | | 1974 | 4,228 | | 1973 | 4,106 | | 1972 | 3,994 | | 1971 | 3,881 | | 1970 | 3,763 | | 1969 | 3,638 | | 1968 | 3,504 | | 1967 | 3,367 | | 1966 | 3,241 | | 1965 | 3,132 | | 1964 | 3,038 | | 1963 | 2,959 | | 1962 | 2,896 | | 1961 | 2,835 | | 1960 | 2,770 |
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