Year	Number
2004-01-01	0.5623
2005-01-01	0.5675
2006-01-01	1.0841
2007-01-01	1.7781
2008-01-01	2.3281
2009-01-01	2.9079
2010-01-01	3.6740
2011-01-01	3.8743
2012-01-01	4.1835
2013-01-01	4.3698
2014-01-01	4.5911
2015-01-01	4.7756
2016-01-01	4.6667