Year	Number
2004-01-01	2.0604
2005-01-01	2.1909
2006-01-01	2.3523
2007-01-01	2.5769
2008-01-01	2.6979
2009-01-01	3.0167
2010-01-01	3.1377
2011-01-01	3.1646
2012-01-01	3.1848
2013-01-01	3.2009
2014-01-01	3.2077
2015-01-01	3.1189
2016-01-01	3.0974
