Year Percent 1996 2.81368 1997 2.12825 1998 2.09824 1999 1.71382 2000 1.85082 2001 6.1004 2002 2.6456 2003 2.3417 2004 2.3801 2005 2.02926 2006 1.83654 2007 1.95007 2008 1.74234 2009 1.68816 2010 1.38215 2011 1.26219 2012 1.22532 2013 1.16944 2014 1.09296 2015 0.9947 2016 0.94463 2017 0.98259