Year	Percent
1999-01-01	25.420
2000-01-01	31.060
2001-01-01	39.115
2002-01-01	50.430
2003-01-01	55.315
2004-01-01	56.575
2005-01-01	54.060
2006-01-01	62.170
2007-01-01	66.930
2008-01-01	60.570
2009-01-01	70.960
2010-01-01	67.255
2011-01-01	54.355
2012-01-01	58.635
2013-01-01	59.975
2014-01-01	60.070
2015-01-01	61.220