Year	Percent
1997-01-01	5.7332700000000000
1998-01-01	4.5475800000000000
1999-01-01	4.7644900000000000
2000-01-01	6.7854800000000010
2001-01-01	10.5813000000000000
2002-01-01	4.0936300000000000
2003-01-01	5.7437000000000000
2004-01-01	5.2151600000000000
2005-01-01	5.9446300000000000
2006-01-01	5.3739200000000000
2007-01-01	4.5500600000000000
2008-01-01	3.5191500000000000
2009-01-01	3.0728800000000000
2010-01-01	3.0977200000000003
2011-01-01	3.2266500000000000
2012-01-01	3.2870199999999996
2013-01-01	3.3961500000000000
2014-01-01	3.4999800000000003
2015-01-01	3.7133599999999998
2016-01-01	4.2058000000000000