| Year | Value | | 2022 | 4,419 | | 2021 | 4,422 | | 2020 | 4,447 | | 2019 | 4,520 | | 2018 | 4,634 | | 2017 | 4,700 | | 2016 | 4,642 | | 2015 | 4,551 | | 2014 | 4,508 | | 2013 | 4,458 | | 2012 | 4,410 | | 2011 | 4,363 | | 2010 | 4,304 | | 2009 | 4,231 | | 2008 | 4,150 | | 2007 | 4,084 | | 2006 | 4,033 | | 2005 | 3,986 | | 2004 | 3,945 | | 2003 | 3,914 | | 2002 | 3,884 | | 2001 | 3,837 | | 2000 | 3,779 | | 1999 | 3,738 | | 1998 | 3,752 | | 1997 | 3,813 | | 1996 | 3,867 | | 1995 | 3,870 | | 1994 | 3,838 | | 1993 | 3,798 | | 1992 | 3,740 | | 1991 | 3,685 | | 1990 | 3,629 | | 1989 | 3,552 | | 1988 | 3,442 | | 1987 | 3,324 | | 1986 | 3,227 | | 1985 | 3,130 | | 1984 | 3,023 | | 1983 | 2,940 | | 1982 | 2,888 | | 1981 | 2,825 | | 1980 | 2,749 | | 1979 | 2,671 | | 1978 | 2,599 | | 1977 | 2,543 | | 1976 | 2,500 | | 1975 | 2,461 | | 1974 | 2,432 | | 1973 | 2,416 | | 1972 | 2,406 | | 1971 | 2,396 | | 1970 | 2,366 | | 1969 | 2,311 | | 1968 | 2,239 | | 1967 | 2,158 | | 1966 | 2,082 | | 1965 | 2,010 | | 1964 | 1,957 | | 1963 | 1,908 | | 1962 | 1,859 | | 1961 | 1,836 | | 1960 | 1,842 |
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