Year	Percent
1999-01-01	45.600
2000-01-01	45.300
2001-01-01	44.525
2002-01-01	43.375
2003-01-01	42.725
2004-01-01	43.525
2005-01-01	42.500
2006-01-01	41.775
2007-01-01	40.825
2008-01-01	40.250
2009-01-01	39.525
2010-01-01	39.450
2011-01-01	39.100
2012-01-01	38.600
2013-01-01	38.325
2014-01-01	38.200
2015-01-01	37.850
2016-01-01	37.000
2017-01-01	36.850