Year	Percent
1998-01-01	7.57375428608848
1999-01-01	5.61633762897317
2000-01-01	4.33207356917271
2001-01-01	3.91462831369113
2002-01-01	4.44375669582247
2003-01-01	4.73706274963014
2004-01-01	4.53851215759498
2005-01-01	4.33823825887979
2006-01-01	4.41182429889231
2007-01-01	4.97944313211315
2008-01-01	6.77326548711566
2009-01-01	12.60812312407730
2010-01-01	14.53337606889960
2011-01-01	15.35064446274980
2012-01-01	15.45023629055060
2013-01-01	13.74729451027290
2014-01-01	11.86001873397030
2015-01-01	9.90613117712233
2016-01-01	8.36800921581580
2017-01-01	6.71179376133051