Year	Number
2004-01-01	1323
2007-01-01	4212
2008-01-01	3329
2010-01-01	11320
2011-01-01	14619
2012-01-01	17293
2013-01-01	57339
2014-01-01	51998
2015-01-01	51796
2016-01-01	51976
2017-01-01	55453