Year Percent 1993 24.57676 1994 24.91156 1995 15.59998 1996 18.41509 1997 18.90869 1998 8.71272 1999 11.12811 2000 8.95793 2001 6.78111 2002 14.0631 2003 19.97642 2004 46.53671 2005 41.38485 2006 32.7154 2007 45.74929 2008 13.73139 2009 18.9631 2010 21.42374 2011 15.24806 2012 19.46379 2013 24.78644 2014 30.06553 2015 24.42019 2016 32.96688