Year	Number
2004-01-01	1.3688
2005-01-01	1.3681
2006-01-01	1.3867
2007-01-01	1.4002
2008-01-01	1.4123
2009-01-01	1.4167
2010-01-01	1.4379
2011-01-01	1.4700
2012-01-01	1.4993
2013-01-01	1.5215
2014-01-01	1.5391
2015-01-01	1.5628
2016-01-01	1.6052
2017-01-01	1.6304