Year	Number
2004-01-01	5422063
2005-01-01	6509570
2006-01-01	7988167
2007-01-01	9682622
2008-01-01	11090877
2009-01-01	11821000
2010-01-01	12544914
2011-01-01	13840690
2012-01-01	14464382
2013-01-01	12965382
2014-01-01	13546206
2015-01-01	16302267
2016-01-01	17527876
2017-01-01	17508739