Year Percent 1992 1.62722 1993 1.91347 1994 2.32695 1995 2.51812 1996 2.16779 1997 1.6963 1998 1.37093 1999 0.99563 2002 0.51726 2003 0.98004 2004 1.44926 2005 1.56397 2006 1.23239 2007 0.91182 2008 0.75027 2009 0.81931 2010 1.21508 2011 1.30096 2012 1.57566 2013 2.24161 2014 2.40808 2015 2.26163 2016 1.82272 2017 1.36266