Year	Number
2006-01-01	1.4975
2007-01-01	1.7360
2008-01-01	1.9136
2009-01-01	2.1383
2010-01-01	2.4714
2011-01-01	2.5061
2012-01-01	2.8432
2013-01-01	3.0186
2014-01-01	3.3520
2015-01-01	3.5690
2016-01-01	4.0465