| Year | Value | | 2022 | 4,951 | | 2021 | 5,101 | | 2020 | 5,275 | | 2019 | 5,475 | | 2018 | 5,678 | | 2017 | 5,846 | | 2016 | 5,946 | | 2015 | 5,958 | | 2014 | 5,882 | | 2013 | 5,732 | | 2012 | 5,524 | | 2011 | 5,271 | | 2010 | 4,997 | | 2009 | 4,715 | | 2008 | 4,440 | | 2007 | 4,195 | | 2006 | 4,012 | | 2005 | 3,889 | | 2004 | 3,818 | | 2003 | 3,787 | | 2002 | 3,794 | | 2001 | 3,806 | | 2000 | 3,821 | | 1999 | 3,846 | | 1998 | 3,843 | | 1997 | 3,835 | | 1996 | 3,861 | | 1995 | 3,924 | | 1994 | 4,025 | | 1993 | 4,157 | | 1992 | 4,285 | | 1991 | 4,374 | | 1990 | 4,473 | | 1989 | 4,582 | | 1988 | 4,644 | | 1987 | 4,656 | | 1986 | 4,602 | | 1985 | 4,464 | | 1984 | 4,249 | | 1983 | 3,998 | | 1982 | 3,730 | | 1981 | 3,474 | | 1980 | 3,287 | | 1979 | 3,187 | | 1978 | 3,121 | | 1977 | 3,045 | | 1976 | 2,956 | | 1975 | 2,848 | | 1974 | 2,719 | | 1973 | 2,570 | | 1972 | 2,404 | | 1971 | 2,235 | | 1970 | 2,105 | | 1969 | 2,087 | | 1968 | 2,155 | | 1967 | 2,234 | | 1966 | 2,303 | | 1965 | 2,350 | | 1964 | 2,376 | | 1963 | 2,382 | | 1962 | 2,373 | | 1961 | 2,357 | | 1960 | 2,337 |
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