Year	Percent
1999-01-01	3.300
2000-01-01	2.800
2001-01-01	2.925
2002-01-01	3.425
2003-01-01	3.700
2004-01-01	4.325
2005-01-01	4.500
2006-01-01	4.125
2007-01-01	3.850
2008-01-01	3.425
2009-01-01	4.925
2010-01-01	4.575
2011-01-01	3.900
2012-01-01	4.350
2013-01-01	5.000
2014-01-01	5.350
2015-01-01	5.450
2016-01-01	5.700
2017-01-01	5.525