Year Percent 2001-01-01 2.47554648251005 2002-01-01 2.58681736514573 2003-01-01 2.89454165114249 2004-01-01 3.32541117229189 2005-01-01 3.88105831960524 2006-01-01 3.70840638840992 2007-01-01 3.25959565877704 2008-01-01 3.31859984553404 2009-01-01 4.40989160671072 2010-01-01 4.55247724224878 2011-01-01 4.15739347613638 2012-01-01 4.26673607480042 2013-01-01 4.33628207360893 2014-01-01 4.31786732828566