Year	Number
2004-01-01	941
2005-01-01	892
2006-01-01	812
2007-01-01	1010
2008-01-01	1426
2009-01-01	1655
2010-01-01	2845
2011-01-01	3285
2012-01-01	13005
2013-01-01	14048
2014-01-01	14371
2015-01-01	14492
2016-01-01	19866