Year Percent 1998-01-01 39.156300000000000 1999-01-01 65.919300000000000 2000-01-01 55.900000000000000 2001-01-01 54.400000000000000 2002-01-01 50.648200000000000 2003-01-01 49.851000000000006 2004-01-01 39.947400000000000 2005-01-01 42.404400000000000 2006-01-01 44.110100000000000 2007-01-01 39.076200000000000 2008-01-01 42.012300000000000 2009-01-01 40.810100000000000 2010-01-01 36.522900000000000 2011-01-01 40.302800000000000 2012-01-01 43.406100000000000 2013-01-01 9.712450000000000 2014-01-01 28.846800000000000 2015-01-01 21.095700000000000 2016-01-01 37.256600000000000