Year % 2005 10.0181902860592 2006 10.2393523448149 2007 10.2540245906716 2008 10.5496437737182 2009 11.9485636678017 2010 10.2993783970849 2011 10.0825402305763 2012 10.1489827569519 2013 10.1473836254435 2014 9.46499496848915 2015 7.68972560551196 2016 8.38895653975315 2017 8.78183018265545 2018 9.10768394993379 2019 9.55200184714006 2020 8.663816526097 2021 8.76978986838747 2022 8.47263101460525