Year	Percent
1999-01-01	4.74872684995661
2000-01-01	4.07910797347673
2001-01-01	4.18698255832979
2002-01-01	4.25241408807515
2003-01-01	4.83765597439080
2004-01-01	5.08430609597925
2005-01-01	4.43941957313899
2006-01-01	3.33424918785254
2007-01-01	3.44788531857748
2008-01-01	3.16609217413507
2009-01-01	6.62632229481355
2010-01-01	8.36033175662541
2011-01-01	7.66731643924626
2012-01-01	7.50621971978526
2013-01-01	6.74515899657698
2014-01-01	6.38151875571821
2015-01-01	5.92212224135988
2016-01-01	5.76721152188563
2017-01-01	5.56755040482616