Year % 2006 6.63117150081856 2007 6.69468124280577 2008 5.91558247139224 2009 9.70857465641102 2010 7.00079451034766 2011 6.58219317797096 2012 7.2270968385805 2013 7.17774019143966 2014 6.28385408719494 2015 7.91375613175869 2016 9.19133073779546 2017 8.59154837379871 2018 8.25772518298564 2019 8.15860942153077 2020 6.21744321567926 2021 6.82689843624374