Year	Percent
1990-01-01	31.413000000000000
1991-01-01	30.644800000000000
1992-01-01	24.431400000000000
1993-01-01	20.550200000000000
1994-01-01	22.085700000000000
1995-01-01	24.209100000000000
1996-01-01	23.733400000000000
1997-01-01	24.110700000000000
1998-01-01	25.528300000000000
1999-01-01	22.712600000000000
2000-01-01	20.053100000000000
2001-01-01	21.095100000000000
2002-01-01	28.014400000000000
2003-01-01	25.754000000000000
2004-01-01	26.324100000000000
2005-01-01	21.782100000000000
2006-01-01	23.668800000000000
2007-01-01	24.859400000000000
2008-01-01	18.747100000000000
2009-01-01	37.449600000000000
2010-01-01	34.734600000000000
2011-01-01	32.792500000000000
2012-01-01	36.748000000000005
2013-01-01	34.611400000000000
2014-01-01	29.245000000000000
2015-01-01	31.478700000000000
2016-01-01	35.634300000000000