Year	Percent
1998-01-01	75.93620300
1999-01-01	72.55009460
2000-01-01	73.81385040
2001-01-01	81.66698837
2002-01-01	79.19498825
2003-01-01	85.95327377
2004-01-01	92.70830536
2005-01-01	72.75102234
2006-01-01	72.74909210
2007-01-01	72.38896942
2008-01-01	72.75555420
2009-01-01	74.15109253
2010-01-01	82.35996246
2011-01-01	81.90304565
2012-01-01	70.64772415
2013-01-01	70.22180939