Year % 2008 8.16375020057627 2009 4.11916461386066 2010 3.06818623299833 2011 2.76420847054839 2012 3.0769175753146 2013 2.88247142261907 2014 2.54111369062263 2015 2.14279238837218 2016 2.17901822396472 2017 2.31775341068148 2018 3.04108365364652 2019 4.111398726013 2020 4.23551043671952 2021 4.16056244801714