Year	Number
2004-01-01	1517
2005-01-01	1999
2006-01-01	2614
2007-01-01	4070
2008-01-01	12235
2009-01-01	7280
2010-01-01	9540
2011-01-01	9829
2012-01-01	13792
2013-01-01	16545
2014-01-01	16078
2015-01-01	9229
2016-01-01	9917