Year % 2004 10.2 2005 12.9 2006 9.6 2007 9.6 2008 9.9 2009 10.2 2010 11.4 2011 11.7 2012 12.7 2013 12.7 2014 12.7 2015 12.5 2016 10.2 2017 11.5 2018 10.9 2019 9.3 2020 10 2021 7.7