| Year | Value | | 2022 | 4,644 | | 2021 | 4,768 | | 2020 | 4,833 | | 2019 | 4,866 | | 2018 | 4,944 | | 2017 | 5,058 | | 2016 | 5,215 | | 2015 | 5,409 | | 2014 | 5,622 | | 2013 | 5,826 | | 2012 | 5,997 | | 2011 | 6,108 | | 2010 | 6,142 | | 2009 | 6,091 | | 2008 | 5,961 | | 2007 | 5,768 | | 2006 | 5,520 | | 2005 | 5,238 | | 2004 | 4,943 | | 2003 | 4,650 | | 2002 | 4,428 | | 2001 | 4,288 | | 2000 | 4,222 | | 1999 | 4,258 | | 1998 | 4,351 | | 1997 | 4,444 | | 1996 | 4,492 | | 1995 | 4,474 | | 1994 | 4,406 | | 1993 | 4,315 | | 1992 | 4,238 | | 1991 | 4,213 | | 1990 | 4,318 | | 1989 | 4,579 | | 1988 | 4,923 | | 1987 | 5,261 | | 1986 | 5,508 | | 1985 | 5,633 | | 1984 | 5,617 | | 1983 | 5,482 | | 1982 | 5,274 | | 1981 | 5,042 | | 1980 | 4,887 | | 1979 | 4,827 | | 1978 | 4,777 | | 1977 | 4,696 | | 1976 | 4,584 | | 1975 | 4,442 | | 1974 | 4,281 | | 1973 | 4,112 | | 1972 | 3,935 | | 1971 | 3,744 | | 1970 | 3,545 | | 1969 | 3,386 | | 1968 | 3,274 | | 1967 | 3,182 | | 1966 | 3,117 | | 1965 | 3,082 | | 1964 | 3,075 | | 1963 | 3,083 | | 1962 | 3,088 | | 1961 | 3,076 | | 1960 | 3,047 |
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