Year % 2007 8.45 2008 13.44 2009 15.4 2010 15.89 2011 12.62 2012 13.64 2013 11.46 2014 10.59 2015 11.32 2016 11.05 2017 12.01 2018 12.37 2019 12.29 2020 10.24 2021 11.65