Year	Percent
2000-01-01	50.0678215067505
2001-01-01	51.0041390809390
2002-01-01	52.0029225636664
2003-01-01	51.1606947928776
2004-01-01	52.3426409589786
2005-01-01	52.5856487750129
2006-01-01	53.2032702829595
2007-01-01	53.3719427679895
2008-01-01	53.3086072371098
2009-01-01	52.2913991389934
2010-01-01	52.6832140451895
2011-01-01	53.1419977920574
2012-01-01	53.5478826803869
2013-01-01	53.9843916511676
2014-01-01	55.0118514284765
2015-01-01	55.7355854492817
2016-01-01	56.1344077731819
2017-01-01	56.8548117820053