Year Percent 2000 10.15 2001 11.75 2002 13.05 2003 12.76 2004 9.62 2005 10.42 2006 8.61 2007 8.87 2008 6.74 2009 6.25 2010 7.58 2011 6.21 2012 7.04 2013 7.7 2014 7.65 2015 8.69 2016 9.08 2017 9.14 2018 9.63 2019 9.95 2020 11.1