| Year | Value | | 2022 | 3,010 | | 2021 | 3,026 | | 2020 | 3,054 | | 2019 | 3,116 | | 2018 | 3,201 | | 2017 | 3,295 | | 2016 | 3,378 | | 2015 | 3,439 | | 2014 | 3,462 | | 2013 | 3,449 | | 2012 | 3,416 | | 2011 | 3,380 | | 2010 | 3,352 | | 2009 | 3,309 | | 2008 | 3,277 | | 2007 | 3,316 | | 2006 | 3,422 | | 2005 | 3,560 | | 2004 | 3,662 | | 2003 | 3,717 | | 2002 | 3,754 | | 2001 | 3,795 | | 2000 | 3,835 | | 1999 | 3,884 | | 1998 | 4,014 | | 1997 | 4,211 | | 1996 | 4,367 | | 1995 | 4,401 | | 1994 | 4,317 | | 1993 | 4,143 | | 1992 | 3,954 | | 1991 | 3,869 | | 1990 | 3,873 | | 1989 | 3,756 | | 1988 | 3,722 | | 1987 | 3,712 | | 1986 | 3,707 | | 1985 | 3,735 | | 1984 | 3,837 | | 1983 | 3,966 | | 1982 | 4,099 | | 1981 | 4,267 | | 1980 | 4,447 | | 1979 | 4,382 | | 1978 | 4,379 | | 1977 | 4,259 | | 1976 | 4,373 | | 1975 | 4,285 | | 1974 | 4,031 | | 1973 | 3,662 | | 1972 | 3,203 | | 1971 | 2,860 | | 1970 | 2,471 | | 1969 | 2,278 | | 1968 | 2,068 | | 1967 | 1,840 | | 1966 | 1,783 | | 1965 | 1,747 | | 1964 | 1,665 | | 1963 | 1,599 | | 1962 | 1,378 | | 1961 | 1,318 | | 1960 | 1,097 |
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