Year % 2009 11.5330478934685 2010 12.2285825263638 2011 12.0101569576645 2012 12.6534987593052 2013 13.5433105997172 2014 13.677327493038 2015 13.9025544488238 2016 14.7981889370371 2017 15.416381791662 2018 15.1918107914897 2019 14.4257972483889 2020 14.4349036142209 2021 13.823886595034 2022 13.6773351621621