Year Percent Change from Year Ago 1998-01-01 4.011813704088330 1999-01-01 -0.205069439004893 2000-01-01 1.210173376432140 2001-01-01 3.316468194744470 2002-01-01 4.522792237533910 2003-01-01 5.418715934397240 2004-01-01 5.258836402657080 2005-01-01 6.750960833988360 2006-01-01 8.452887747735870 2007-01-01 10.799577048688700 2008-01-01 5.629779024911700 2009-01-01 -5.422542313329600 2010-01-01 5.041716665038190 2011-01-01 2.819099517577570 2012-01-01 1.657148687194100 2013-01-01 1.490646437820090 2014-01-01 2.750335016886330 2015-01-01 3.850100604400250 2016-01-01 3.324695295964020 2017-01-01 3.400166311079870