Year % 2008 8.49660483267178 2009 7.74991935028793 2010 6.69884374235195 2011 7.57910664692136 2012 7.97137046755677 2013 7.41635746688502 2014 6.86384985813915 2015 6.33740826221559 2016 5.61605826300673 2017 5.19387817397176 2018 5.72640411911641 2019 5.76740721151145 2020 7.18670543745059 2021 7.51457650170697