Year	Months
2004-01-01	3.14069193717611
2005-01-01	2.74398507413490
2006-01-01	2.70619074024609
2007-01-01	2.70875964880103
2008-01-01	2.22347886470223
2009-01-01	2.71606720556734
2010-01-01	2.85683799320974
2011-01-01	2.93587667336564
2012-01-01	2.85261229939507
2013-01-01	2.85978099032385
2014-01-01	2.51246913418400
2015-01-01	2.57283066726961
2016-01-01	2.62151651809894
2017-01-01	2.85943026460736
2018-01-01	2.91845684386540
2019-01-01	3.04686681102730
