Year	Percent
1999-01-01	2.750
2000-01-01	3.025
2001-01-01	2.925
2002-01-01	3.125
2003-01-01	2.825
2004-01-01	3.100
2005-01-01	3.875
2006-01-01	3.975
2007-01-01	4.400
2008-01-01	5.100
2009-01-01	6.475
2010-01-01	7.900
2011-01-01	9.175
2012-01-01	8.400
2013-01-01	8.050
2014-01-01	6.375
2015-01-01	5.800
2016-01-01	4.400
2017-01-01	3.600