Year	Percent
1986-01-01	8.16532915355929
1987-01-01	7.70966591686080
1988-01-01	10.05672048509270
1989-01-01	12.97146685581000
1990-01-01	13.49410923634950
1991-01-01	17.18242043142020
1992-01-01	16.89336759097140
1993-01-01	16.35336692680090
1994-01-01	14.76705455222030
1995-01-01	12.19510842637060
1996-01-01	11.50781132752000
1997-01-01	13.35737406250770
1998-01-01	13.83600683253900
1999-01-01	12.99199869110600
2000-01-01	12.35412616451230
2001-01-01	11.86637751977750
2002-01-01	11.67771488774540
2003-01-01	10.62104673748300
2004-01-01	10.49077853962680
2005-01-01	10.21221476064440
2006-01-01	10.41860386930320
2007-01-01	9.84600351210981
2008-01-01	10.52151983762670
2009-01-01	16.26273896857510
2010-01-01	16.72386000898070
2011-01-01	14.93189454588090
2012-01-01	16.65723207110050
2013-01-01	15.41468292658130
2014-01-01	14.56922390882290
2015-01-01	13.67697602872050
2016-01-01	13.37367967791890
2017-01-01	13.02342530910480