Year	Number
2004-01-01	3.7265
2005-01-01	3.9525
2006-01-01	3.0793
2007-01-01	3.2918
2008-01-01	3.4895
2009-01-01	3.3647
2010-01-01	3.2585
2011-01-01	3.3237
2012-01-01	3.2907
2013-01-01	3.2779
2014-01-01	3.3915
2015-01-01	2.9658
2016-01-01	2.9566
2017-01-01	2.8250