Year | Value | 2021 | 464 | 2020 | 6,295 | 2019 | 10,111 | 2018 | 11,435 | 2017 | 11,748 | 2016 | 12,187 | 2015 | 11,768 | 2014 | 11,755 | 2013 | 11,736 | 2012 | 11,826 | 2011 | 12,297 | 2010 | 11,321 | 2009 | 11,237 | 2008 | 15,974 | 2007 | 12,221 | 2006 | 12,471 | 2005 | 9,691 | 2004 | 7,848 | 2003 | 4,577 | 2002 | 2,252 | 2001 | 6,687 | 2000 | 12,158 | 1999 | 15,200 | 1998 | 14,600 | 1997 | 12,700 | 1996 | 13,600 | 1995 | 14,700 | 1994 | 16,900 | 1993 | 17,300 | 1992 | 16,500 | 1991 | 15,300 | 1990 | 37,200 | 1989 | 35,900 | 1988 | 39,800 | 1987 | 40,000 | 1986 | 38,700 | 1985 | 37,000 | 1984 | 39,100 | 1983 | 38,000 | 1982 | 34,500 | 1981 | 27,000 | 1980 | 27,000 | 1979 | 26,600 | 1978 | 22,800 | 1977 | 22,200 | 1976 | 22,000 | 1975 | 20,100 | 1974 | 19,800 |
|