Year	Percent
2000-01-01	49.2
2001-01-01	47.4
2002-01-01	43.9
2003-01-01	44.1
2004-01-01	45.1
2005-01-01	46.8
2006-01-01	46.8
2007-01-01	46.8
2008-01-01	46.8
2009-01-01	46.8
2010-01-01	46.8
2011-01-01	48.6
2012-01-01	45.7
2013-01-01	56.4
2014-01-01	58.1
2015-01-01	56.8