Year	Months
2004-01-01	8.21857464014786
2005-01-01	7.01090800434478
2006-01-01	5.57345725011694
2007-01-01	5.11818740492619
2008-01-01	5.56655184996320
2009-01-01	6.40351829228831
2010-01-01	5.47706439474146
2011-01-01	6.41581414898382
2012-01-01	6.84954397736989
2013-01-01	6.00203213853386
2014-01-01	8.44264400223698
2015-01-01	9.15353938243390
2016-01-01	6.58888263488478
2017-01-01	6.28396633817977
2018-01-01	6.67424299295938
2019-01-01	6.02127676782395