Year Percent 1999 13.32 2000 9.74 2001 8.69 2002 8.1 2003 9.57 2004 10.08 2005 8.66 2006 8.91 2007 6.23 2008 4.54 2009 7.83 2010 9.0845 2011 7.7257 2012 6.821 2013 6.0278 2014 4.623 2015 4.4524 2016 5.4643 2017 4.8282