Year	Percent
1997-01-01	0.262847
1998-01-01	0.317880
1999-01-01	32.107200
2000-01-01	37.878100
2001-01-01	40.362300
2002-01-01	52.952100
2003-01-01	48.716300
2004-01-01	58.845800
2005-01-01	53.997900
2006-01-01	56.346100
2007-01-01	66.551200
2008-01-01	55.952400
2009-01-01	61.771300
2010-01-01	60.206400
2011-01-01	50.849600
2012-01-01	57.005500
2013-01-01	48.052500
2014-01-01	40.422400
2015-01-01	43.713600
2016-01-01	44.785600