Year Percent 2003 0.02182 2004 -0.01324 2005 0.0239 2006 0 2007 0 2008 0.70261 2009 0.64788 2010 0.4499 2011 0.39152 2012 0.31651 2013 0.00265 2014 -0.00009 2015 -0.00695 2016 -0.07589 2017 -0.05186