Year Percent 1999-01-01 0.28252100000000000 2000-01-01 0.30392100000000000 2001-01-01 0.33060800000000000 2002-01-01 0.34405100000000000 2003-01-01 0.37119100000000000 2004-01-01 0.43335700000000000 2005-01-01 0.42098100000000005 2006-01-01 0.45557600000000004 2007-01-01 0.39940900000000000 2008-01-01 0.41771600000000000 2009-01-01 0.37455400000000000 2010-01-01 0.39353200000000000 2011-01-01 0.38658800000000000 2012-01-01 0.42450500000000000 2013-01-01 0.46973700000000000