Year Percent 1996-01-01 1.6941200000000000 1997-01-01 1.3614800000000000 1998-01-01 1.2436800000000000 1999-01-01 1.4142000000000000 2000-01-01 2.0056400000000000 2001-01-01 1.7196599999999997 2002-01-01 2.1896700000000000 2003-01-01 2.3443200000000000 2004-01-01 2.0945200000000000 2005-01-01 1.5957299999999999 2006-01-01 1.8435099999999998 2007-01-01 2.1030300000000000 2008-01-01 1.7668400000000002 2009-01-01 2.9027400000000000 2010-01-01 4.0565800000000000 2011-01-01 3.2146800000000000 2012-01-01 1.8521900000000002 2013-01-01 1.7765700000000000 2014-01-01 1.7169400000000001 2015-01-01 1.6577800000000000 2016-01-01 1.7318200000000001