Year Percent 1998 6.34551 1999 7.80128 2000 1.01038 2001 4.24366 2002 -0.93946 2003 2.52035 2004 3.23933 2005 1.07143 2006 2.54396 2007 5.83296 2008 0.39758 2009 -13.88021 2010 -5.84155 2011 -10.57268 2012 -8.73625 2013 -4.20036 2014 -1.95655 2015 -0.43832 2016 0.22725 2017 0.63893