Year	Number
2004-01-01	93
2005-01-01	150
2006-01-01	237
2007-01-01	384
2008-01-01	588
2009-01-01	870
2010-01-01	1463
2011-01-01	2410
2012-01-01	2533
2013-01-01	2958
2014-01-01	3375
2015-01-01	3823