Year	Months
2004-01-01	3.10700068484125
2005-01-01	3.56773860013564
2006-01-01	4.02337604164724
2007-01-01	4.15902373213369
2008-01-01	3.44774395091121
2009-01-01	5.26220877431588
2010-01-01	5.20425548931071
2011-01-01	5.16736374246559
2012-01-01	5.95405449816145
2013-01-01	4.77915524068458
2014-01-01	2.98462507112584
2015-01-01	2.25840964826393
2016-01-01	1.38622564318195
2017-01-01	2.80660858511943
2018-01-01	2.93441229107603
2019-01-01	2.96915367833291
