Year % 2005 8.20906380726336 2006 6.47013971237757 2007 5.31015886166558 2008 5.01177403541518 2009 5.78360747367995 2010 7.01547424164959 2011 7.0887209730083 2012 7.75197194482716 2013 8.94793807670442 2014 9.04960051895585 2015 7.09795110848624 2016 5.29469189649343 2017 4.06994769176586 2018 3.35528926091019 2019 3.20817921458462 2020 3.66282402946949 2021 3.43931378803346 2022 3.69898803529553