940
200
400
600
800
1,000
1,200
1,400
1,600
1,800
2,000
1,910
1987
1,877
1988
1,865
1989
2,113
1990
2,086
1991
2,061
1992
2,010
1993
1,997
1994
1,952
1995
1,930
1996
1,947
1997
1,893
1998
1,836
1999
1,777
2000
1,738
2001
1,689
2002
1,615
2003
1,572
2004
1,510
2005
1,439
2006
1,390
2007
1,364
2008
1,390
2009
1,304
2010
1,230
2011
1,130
2012
1,044
2013
932
2014
940
2015
* Nieuwe vondsten verklaren toenames
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