| Year | Value | | 2022 | 3,656 | | 2021 | 3,579 | | 2020 | 3,567 | | 2019 | 3,609 | | 2018 | 3,684 | | 2017 | 3,779 | | 2016 | 3,877 | | 2015 | 3,956 | | 2014 | 3,997 | | 2013 | 4,028 | | 2012 | 4,069 | | 2011 | 4,119 | | 2010 | 4,177 | | 2009 | 4,232 | | 2008 | 4,269 | | 2007 | 4,282 | | 2006 | 4,276 | | 2005 | 4,261 | | 2004 | 4,254 | | 2003 | 4,260 | | 2002 | 4,280 | | 2001 | 4,319 | | 2000 | 4,376 | | 1999 | 4,452 | | 1998 | 4,530 | | 1997 | 4,590 | | 1996 | 4,615 | | 1995 | 4,599 | | 1994 | 4,547 | | 1993 | 4,468 | | 1992 | 4,367 | | 1991 | 4,235 | | 1990 | 4,103 | | 1989 | 3,972 | | 1988 | 3,808 | | 1987 | 3,634 | | 1986 | 3,476 | | 1985 | 3,348 | | 1984 | 3,260 | | 1983 | 3,171 | | 1982 | 3,059 | | 1981 | 2,924 | | 1980 | 2,743 | | 1979 | 2,524 | | 1978 | 2,330 | | 1977 | 2,175 | | 1976 | 2,046 | | 1975 | 1,965 | | 1974 | 1,923 | | 1973 | 1,903 | | 1972 | 1,893 | | 1971 | 1,884 | | 1970 | 1,874 | | 1969 | 1,863 | | 1968 | 1,851 | | 1967 | 1,844 | | 1966 | 1,835 | | 1965 | 1,826 | | 1964 | 1,820 | | 1963 | 1,817 | | 1962 | 1,812 | | 1961 | 1,804 | | 1960 | 1,801 |
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