Year	Number
2004-01-01	740
2005-01-01	745
2006-01-01	1288
2007-01-01	3372
2008-01-01	3380
2009-01-01	4375
2010-01-01	4624
2011-01-01	4972
2012-01-01	5131
2013-01-01	5422
2014-01-01	5937
2015-01-01	6186
2016-01-01	6383