Year % (cumulative) 2006 0 2007 0 2008 0 2009 0 2010 0 2011 0 2012 0 2013 17.9176807403564 2014 18.7445392608643 2015 19.1072273254395 2016 19.2677593231201 2017 20.123722076416 2018 20.7168445587158 2019 21.2703380584717 2020 21.8941097259521 2021 21.8675842285156 2022 22.3140411376953