Year	Percent
1998-01-01	18.086600000000000
1999-01-01	24.887900000000000
2000-01-01	31.400000000000000
2001-01-01	15.300000000000000
2002-01-01	18.037800000000000
2003-01-01	25.000999999999998
2004-01-01	18.354200000000000
2005-01-01	20.102200000000000
2006-01-01	23.156200000000000
2007-01-01	31.909600000000000
2008-01-01	29.750200000000000
2009-01-01	30.174500000000000
2010-01-01	29.775700000000000
2011-01-01	28.946600000000000
2012-01-01	39.765500000000000
2013-01-01	38.054900000000000
2014-01-01	37.558500000000000
2015-01-01	39.642800000000000
2016-01-01	34.111200000000000