Year	Percent
1998-01-01	14.600000380
1999-01-01	15.300000190
2000-01-01	17.500000000
2001-01-01	16.799999240
2002-01-01	17.200000760
2003-01-01	18.700000760
2004-01-01	19.399999620
2005-01-01	15.699999810
2006-01-01	10.899999620
2007-01-01	7.900000095
2008-01-01	6.000000000
2009-01-01	5.500000000
2010-01-01	4.800000191
2011-01-01	4.800000191
2012-01-01	5.000000000
2013-01-01	5.900000095