Year	Percent
1998-01-01	1.100000
1999-01-01	1.200000
2000-01-01	1.300000
2001-01-01	1.500000
2002-01-01	1.600000
2003-01-01	1.200000
2004-01-01	0.700000
2005-01-01	0.500000
2006-01-01	0.400000
2007-01-01	0.400000
2008-01-01	0.800000
2009-01-01	1.300000
2010-01-01	1.200000
2011-01-01	0.800000
2012-01-01	0.700000
2013-01-01	0.600000
2014-01-01	0.500000
2015-01-01	0.500000
2016-01-01	0.591882