Year % 2006 12.1641165032584 2007 13.253396304689 2008 10.5651865400198 2009 10.1553246301666 2010 11.3867483270508 2011 11.3539428989383 2012 11.2065653107062 2013 11.1033192496814 2014 10.7596001657697 2015 11.6900887415558 2016 10.6778631000913 2017 11.1702124453155 2018 11.2154104719723 2019 10.5466541274415 2020 10.1809531850719 2021 11.1937886550086