Year % 2006 21.598496792969907 2007 33.60287417577257 2008 34.351029728479084 2009 30.883046296252036 2010 26.15993494367083 2011 36.20741385121379 2012 34.69010584414149 2013 25.226266140362842 2014 21.73593643542047 2015 20.836006012970955 2016 25.869464435311833 2017 27.537310119872217 2018 25.97412384654241 2019 21.414799483801197 2020 18.468375330237382 2021 16.13269471326266 2022 16.989600672894408 2023 16.639209293070355