Year	Percent
1999-01-01	37.18
2000-01-01	43.16
2001-01-01	44.89
2002-01-01	45.17
2003-01-01	48.37
2004-01-01	52.05
2005-01-01	62.43
2006-01-01	63.93
2007-01-01	58.53
2008-01-01	45.52
2009-01-01	49.69
2010-01-01	50.91
2011-01-01	43.40
2012-01-01	45.32
2013-01-01	44.86
2014-01-01	47.37
2015-01-01	47.22
2016-01-01	47.30