Year	Percent
1998-01-01	36.838300000000000
1999-01-01	43.227200000000000
2000-01-01	37.300000000000000
2001-01-01	38.600000000000000
2002-01-01	38.545600000000000
2003-01-01	35.462200000000000
2004-01-01	34.917400000000000
2005-01-01	39.208400000000000
2006-01-01	43.848800000000000
2007-01-01	49.287800000000000
2008-01-01	44.820500000000000
2009-01-01	51.653800000000000
2010-01-01	57.111400000000000
2011-01-01	58.814600000000000
2012-01-01	57.976000000000006
2013-01-01	62.326500000000000
2014-01-01	60.333999999999996
2015-01-01	57.597000000000000
2016-01-01	59.233200000000000