| Year | Value | | 2024 | 4,506 | | 2023 | 4,303 | | 2022 | 4,128 | | 2021 | 3,996 | | 2020 | 3,949 | | 2019 | 3,994 | | 2018 | 4,097 | | 2017 | 4,231 | | 2016 | 4,350 | | 2015 | 4,422 | | 2014 | 4,449 | | 2013 | 4,439 | | 2012 | 4,383 | | 2011 | 4,374 | | 2010 | 4,465 | | 2009 | 4,582 | | 2008 | 4,691 | | 2007 | 4,772 | | 2006 | 4,811 | | 2005 | 4,827 | | 2004 | 4,847 | | 2003 | 4,871 | | 2002 | 4,879 | | 2001 | 4,857 | | 2000 | 4,817 | | 1999 | 4,758 | | 1998 | 4,697 | | 1997 | 4,666 | | 1996 | 4,700 | | 1995 | 4,809 | | 1994 | 4,964 | | 1993 | 5,134 | | 1992 | 5,288 | | 1991 | 5,392 | | 1990 | 5,413 | | 1989 | 5,331 | | 1988 | 5,146 | | 1987 | 4,884 | | 1986 | 4,644 | | 1985 | 4,500 | | 1984 | 4,434 | | 1983 | 4,410 | | 1982 | 4,402 | | 1981 | 4,389 | | 1980 | 4,357 | | 1979 | 4,298 | | 1978 | 4,209 | | 1977 | 4,095 | | 1976 | 3,946 | | 1975 | 3,778 |
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