Year	Percent
1998-01-01	33.8395
1999-01-01	29.4841
2000-01-01	31.3000
2001-01-01	27.1000
2002-01-01	21.5994
2003-01-01	18.7696
2004-01-01	15.8899
2005-01-01	20.6803
2006-01-01	23.5800
2007-01-01	26.7156
2008-01-01	19.8049
2009-01-01	22.7439
2010-01-01	21.4241
2011-01-01	21.9266
2012-01-01	18.6097
2013-01-01	19.9106
2014-01-01	21.6306