Year Percent 2002 9.3852 2003 9.7838 2004 8.6715 2005 9.3267 2006 7.4794 2007 8.8597 2008 7.8714 2009 7.9866 2010 7.4674 2011 7.7858 2012 6.4079 2013 6.7311 2014 7.4977 2015 7.2133 2016 8.6958 2017 8.6623