Year	Number
2004-01-01	1.5570
2005-01-01	1.5892
2006-01-01	1.7147
2007-01-01	1.8288
2008-01-01	1.8675
2009-01-01	2.0305
2010-01-01	2.2645
2011-01-01	2.4787
2012-01-01	2.6998
2013-01-01	3.2079
2014-01-01	3.1390
2015-01-01	3.1767
2016-01-01	3.1716