Year Percent 1991-01-01 42.0610008239746 1992-01-01 42.9949989318848 1993-01-01 43.2249984741211 1994-01-01 41.0050010681152 1995-01-01 39.6440010070801 1996-01-01 41.6319999694824 1997-01-01 42.4690017700195 1998-01-01 41.1100006103516 1999-01-01 43.8310012817383 2000-01-01 44.0550003051758 2001-01-01 44.4389991760254 2002-01-01 44.5999984741211 2003-01-01 44.8209991455078 2004-01-01 45.5130004882813 2005-01-01 45.2080001831055 2006-01-01 45.5229988098145 2007-01-01 45.4140014648438 2008-01-01 45.1150016784668 2009-01-01 45.3279991149902 2010-01-01 45.3370018005371 2011-01-01 45.3639984130859 2012-01-01 44.7350006103516 2013-01-01 44.6790008544922 2014-01-01 44.4580001831055 2015-01-01 44.3400001525879 2016-01-01 44.4729995727539 2017-01-01 44.4239997863770