Year	Percent
1999-01-01	60.550
2000-01-01	59.150
2001-01-01	60.100
2002-01-01	57.800
2003-01-01	56.150
2004-01-01	54.800
2005-01-01	53.525
2006-01-01	52.100
2007-01-01	51.025
2008-01-01	49.625
2009-01-01	48.550
2010-01-01	47.850
2011-01-01	47.200
2012-01-01	46.550
2013-01-01	46.625
2014-01-01	46.900
2015-01-01	46.900
2016-01-01	46.950
2017-01-01	47.375