Year % 2005 11.31 2007 11.41 2008 12.6 2009 13.72 2010 13.72 2011 14.12 2012 13.87 2013 15.81 2014 15.96 2015 17.03 2016 15.78 2017 16.86 2018 17 2019 15.35 2020 13.82 2021 15.36