| Year | Value | | 2023 | 41,935 | | 2022 | 40,834 | | 2021 | 40,403 | | 2020 | 39,646 | | 2019 | 38,304 | | 2018 | 36,837 | | 2017 | 35,416 | | 2016 | 33,995 | | 2015 | 32,584 | | 2014 | 31,135 | | 2013 | 29,675 | | 2012 | 28,241 | | 2011 | 26,831 | | 2010 | 25,444 | | 2009 | 24,051 | | 2008 | 22,673 | | 2007 | 21,384 | | 2006 | 20,227 | | 2005 | 19,171 | | 2004 | 18,158 | | 2003 | 17,206 | | 2002 | 16,315 | | 2001 | 15,468 | | 2000 | 14,682 | | 1999 | 13,961 | | 1998 | 13,272 | | 1997 | 12,609 | | 1996 | 11,979 | | 1995 | 11,374 | | 1994 | 10,766 | | 1993 | 10,176 | | 1992 | 9,612 | | 1991 | 9,055 | | 1990 | 8,515 | | 1989 | 7,999 | | 1988 | 7,505 | | 1987 | 7,032 | | 1986 | 6,597 | | 1985 | 6,200 | | 1984 | 5,820 | | 1983 | 5,464 | | 1982 | 5,150 | | 1981 | 4,880 | | 1980 | 4,650 | | 1979 | 4,481 | | 1978 | 4,421 | | 1977 | 4,420 | | 1976 | 4,698 | | 1975 | 5,948 | | 1974 | 6,860 |
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