| Year | Value | | 2024 | 19,042 | | 2023 | 18,382 | | 2022 | 17,669 | | 2021 | 16,930 | | 2020 | 16,289 | | 2019 | 15,749 | | 2018 | 15,234 | | 2017 | 14,789 | | 2016 | 14,408 | | 2015 | 14,116 | | 2014 | 13,945 | | 2013 | 13,875 | | 2012 | 13,855 | | 2011 | 13,853 | | 2010 | 13,791 | | 2009 | 13,578 | | 2008 | 13,234 | | 2007 | 12,815 | | 2006 | 12,324 | | 2005 | 11,766 | | 2004 | 11,172 | | 2003 | 10,567 | | 2002 | 9,966 | | 2001 | 9,386 | | 2000 | 8,847 | | 1999 | 8,329 | | 1998 | 7,786 | | 1997 | 7,211 | | 1996 | 6,621 | | 1995 | 6,032 | | 1994 | 5,458 | | 1993 | 4,915 | | 1992 | 4,418 | | 1991 | 3,975 | | 1990 | 3,597 | | 1989 | 3,372 | | 1988 | 3,291 | | 1987 | 3,264 | | 1986 | 3,277 | | 1985 | 3,319 | | 1984 | 3,383 | | 1983 | 3,466 | | 1982 | 3,560 | | 1981 | 3,662 | | 1980 | 3,811 | | 1979 | 3,928 | | 1978 | 3,964 | | 1977 | 4,010 | | 1976 | 4,085 | | 1975 | 4,195 |
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