Year	Percent
1999-01-01	8.2000
2000-01-01	17.3000
2001-01-01	15.3000
2002-01-01	24.4000
2003-01-01	30.9000
2004-01-01	28.2000
2005-01-01	23.7000
2006-01-01	21.9000
2007-01-01	18.9000
2008-01-01	18.0000
2009-01-01	20.6000
2010-01-01	18.9721
2011-01-01	16.5506
2012-01-01	17.8862
2013-01-01	15.2836
2014-01-01	16.2812
2015-01-01	15.5695
2016-01-01	15.5665