Year	Percent
1999-01-01	20.741100000000000
2000-01-01	18.015400000000000
2001-01-01	15.182600000000000
2002-01-01	12.516300000000000
2003-01-01	18.065200000000000
2004-01-01	20.858900000000000
2005-01-01	25.338200000000000
2006-01-01	31.242700000000000
2007-01-01	36.249000000000000
2008-01-01	18.673200000000000
2009-01-01	27.709100000000000
2010-01-01	32.746000000000000
2011-01-01	29.008000000000003
2012-01-01	32.942000000000000
2013-01-01	38.779500000000000
2014-01-01	38.850000000000000
2015-01-01	37.284200000000000
2016-01-01	37.568900000000000