Year Percent 2001-01-01 0.44 2002-01-01 0.53 2003-01-01 0.63 2004-01-01 0.63 2005-01-01 0.60 2006-01-01 0.60 2007-01-01 0.58 2008-01-01 0.80 2009-01-01 0.89 2010-01-01 0.89 2011-01-01 4.48 2012-01-01 4.43 2013-01-01 3.84 2014-01-01 3.87