| Year | Value | | 2022 | 4,163 | | 2021 | 4,096 | | 2020 | 4,111 | | 2019 | 4,246 | | 2018 | 4,404 | | 2017 | 4,494 | | 2016 | 4,536 | | 2015 | 4,486 | | 2014 | 4,354 | | 2013 | 4,188 | | 2012 | 3,927 | | 2011 | 3,594 | | 2010 | 3,405 | | 2009 | 3,350 | | 2008 | 3,311 | | 2007 | 3,329 | | 2006 | 3,386 | | 2005 | 3,384 | | 2004 | 3,324 | | 2003 | 3,258 | | 2002 | 3,196 | | 2001 | 3,136 | | 2000 | 3,124 | | 1999 | 3,147 | | 1998 | 3,161 | | 1997 | 3,157 | | 1996 | 3,141 | | 1995 | 3,143 | | 1994 | 3,153 | | 1993 | 3,158 | | 1992 | 3,192 | | 1991 | 3,253 | | 1990 | 3,306 | | 1989 | 3,327 | | 1988 | 3,299 | | 1987 | 3,236 | | 1986 | 3,161 | | 1985 | 3,109 | | 1984 | 3,105 | | 1983 | 3,159 | | 1982 | 3,260 | | 1981 | 3,371 | | 1980 | 3,460 | | 1979 | 3,520 | | 1978 | 3,540 | | 1977 | 3,509 | | 1976 | 3,461 | | 1975 | 3,442 | | 1974 | 3,453 | | 1973 | 3,450 | | 1972 | 3,432 | | 1971 | 3,399 | | 1970 | 3,342 | | 1969 | 3,286 | | 1968 | 3,235 | | 1967 | 3,183 | | 1966 | 3,130 | | 1965 | 3,063 | | 1964 | 2,992 | | 1963 | 2,949 | | 1962 | 2,930 | | 1961 | 2,920 | | 1960 | 2,937 |
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