Year	Percent
1999-01-01	44.7653394883631
2000-01-01	43.6792631816971
2001-01-01	43.9318899577369
2002-01-01	44.2186990227544
2003-01-01	44.9420050302794
2004-01-01	45.7927644352600
2005-01-01	47.2197039992179
2006-01-01	49.3893115180244
2007-01-01	50.5135913487565
2008-01-01	52.0359488257033
2009-01-01	50.4689575818306
2010-01-01	48.7458259581649
2011-01-01	49.2229163492305
2012-01-01	49.5278896572688
2013-01-01	49.1388467374810