Year	Percent
2000-01-01	57.8486428985378
2001-01-01	58.3951607175356
2002-01-01	59.5473992608917
2003-01-01	57.7528315663985
2004-01-01	58.8422781456723
2005-01-01	58.2926682832102
2006-01-01	58.3586596299520
2007-01-01	59.5834090394213
2008-01-01	60.1414243600353
2009-01-01	59.7827071060841
2010-01-01	60.6307220043030
2011-01-01	62.2931651249736
2012-01-01	63.0799649008390
2013-01-01	64.3375092371395
2014-01-01	65.7453277294728
2015-01-01	65.9923520823555
2016-01-01	66.1614155827608
2017-01-01	67.4426136543176