Year	Number
2004-01-01	0.5265
2005-01-01	0.5748
2006-01-01	1.0174
2007-01-01	1.1043
2008-01-01	1.4469
2009-01-01	1.5098
2010-01-01	1.5103
2011-01-01	1.5274
2012-01-01	1.5217
2013-01-01	1.5090
2014-01-01	1.4540
2015-01-01	1.4152
2016-01-01	1.3986