| Year | Value | | 2023 | 3,836 | | 2022 | 3,887 | | 2021 | 3,942 | | 2020 | 3,997 | | 2019 | 4,013 | | 2018 | 3,997 | | 2017 | 4,000 | | 2016 | 4,025 | | 2015 | 4,072 | | 2014 | 4,133 | | 2013 | 4,205 | | 2012 | 4,278 | | 2011 | 4,345 | | 2010 | 4,428 | | 2009 | 4,518 | | 2008 | 4,593 | | 2007 | 4,666 | | 2006 | 4,740 | | 2005 | 4,802 | | 2004 | 4,787 | | 2003 | 4,709 | | 2002 | 4,624 | | 2001 | 4,510 | | 2000 | 4,353 | | 1999 | 4,162 | | 1998 | 3,970 | | 1997 | 3,800 | | 1996 | 3,653 | | 1995 | 3,506 | | 1994 | 3,324 | | 1993 | 3,115 | | 1992 | 2,937 | | 1991 | 2,800 | | 1990 | 2,679 | | 1989 | 2,565 | | 1988 | 2,454 | | 1987 | 2,331 | | 1986 | 2,215 | | 1985 | 2,131 | | 1984 | 2,074 | | 1983 | 2,044 | | 1982 | 2,047 | | 1981 | 2,058 | | 1980 | 2,044 | | 1979 | 2,001 | | 1978 | 1,948 | | 1977 | 1,882 | | 1976 | 1,795 | | 1975 | 1,705 | | 1974 | 1,613 |
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