| Year | Value | | 2022 | 5,295 | | 2021 | 5,499 | | 2020 | 5,746 | | 2019 | 5,898 | | 2018 | 6,347 | | 2017 | 6,932 | | 2016 | 7,049 | | 2015 | 7,066 | | 2014 | 7,015 | | 2013 | 6,921 | | 2012 | 6,814 | | 2011 | 6,680 | | 2010 | 6,468 | | 2009 | 6,258 | | 2008 | 6,073 | | 2007 | 5,836 | | 2006 | 5,544 | | 2005 | 5,213 | | 2004 | 4,905 | | 2003 | 4,676 | | 2002 | 4,473 | | 2001 | 4,396 | | 2000 | 4,498 | | 1999 | 4,617 | | 1998 | 4,692 | | 1997 | 4,639 | | 1996 | 4,441 | | 1995 | 4,196 | | 1994 | 3,968 | | 1993 | 3,772 | | 1992 | 3,610 | | 1991 | 3,512 | | 1990 | 3,477 | | 1989 | 3,486 | | 1988 | 3,521 | | 1987 | 3,541 | | 1986 | 3,512 | | 1985 | 3,440 | | 1984 | 3,332 | | 1983 | 3,212 | | 1982 | 3,093 | | 1981 | 2,977 | | 1980 | 2,889 | | 1979 | 2,819 | | 1978 | 2,778 | | 1977 | 2,759 | | 1976 | 2,729 | | 1975 | 2,701 | | 1974 | 2,667 | | 1973 | 2,617 | | 1972 | 2,606 | | 1971 | 2,587 | | 1970 | 2,534 | | 1969 | 2,491 | | 1968 | 2,451 | | 1967 | 2,421 | | 1966 | 2,409 | | 1965 | 2,406 | | 1964 | 2,400 | | 1963 | 2,398 | | 1962 | 2,394 | | 1961 | 2,386 | | 1960 | 2,400 |
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