Year	Number
2004-01-01	1.9688
2005-01-01	1.9688
2006-01-01	2.0509
2007-01-01	2.2970
2008-01-01	2.2970
2009-01-01	2.2970
2010-01-01	2.4610
2011-01-01	2.5431
2012-01-01	2.7892
2013-01-01	2.8712
2014-01-01	3.0353
2015-01-01	2.9532