Year	Percent
1998-01-01	15.6000
1999-01-01	15.5000
2000-01-01	13.8000
2001-01-01	14.8000
2002-01-01	16.6000
2003-01-01	18.8000
2004-01-01	18.6000
2005-01-01	17.9000
2006-01-01	19.0000
2007-01-01	18.8000
2008-01-01	17.7000
2009-01-01	18.7000
2010-01-01	16.8864
2011-01-01	16.3317
2012-01-01	16.4308
2013-01-01	16.1148
2014-01-01	16.6709
2015-01-01	16.3587
2016-01-01	17.1584