Year % 2001 13.46 2002 13.46 2003 13.74 2004 14.86 2005 13.59 2006 12.08 2007 11.93 2008 13.53 2009 9.62 2010 10.53 2011 10.29 2012 8.47 2013 12.23 2014 9.96 2017 12.84 2018 12.19 2019 8.9 2020 10.04 2021 10.34