Year Percent 1993-01-01 1.8746300000000000 1994-01-01 2.1829600000000000 1995-01-01 2.0037300000000000 1996-01-01 1.9297300000000000 1997-01-01 2.2708800000000000 1998-01-01 2.3694100000000000 1999-01-01 2.1208200000000000 2000-01-01 1.9478600000000000 2001-01-01 2.2949700000000000 2002-01-01 2.5524400000000003 2003-01-01 2.6799900000000000 2004-01-01 3.0358300000000000 2005-01-01 3.0914700000000000 2006-01-01 2.7546800000000000 2007-01-01 2.9474800000000000 2008-01-01 2.5771800000000000 2009-01-01 2.6355000000000000 2010-01-01 2.6472300000000000 2011-01-01 2.6225900000000000 2012-01-01 2.8384300000000000 2013-01-01 2.7421500000000000 2014-01-01 2.9259700000000000 2015-01-01 2.8911900000000000 2016-01-01 2.9764300000000000