Year % 2004 12.6 2005 14.1 2006 11.1 2007 13.9 2008 15.1 2009 15.5 2010 16.1 2011 14.6 2012 14.3 2013 13.8 2014 13.3 2015 11.7 2016 12.5 2017 12.8 2018 11.9 2019 11.9 2020 12.2 2021 12.3