Year % 1996 7.95 2006 11.23 2007 11.42 2008 11.1 2009 11.56 2010 11.59 2011 11.71 2012 10.98 2013 11.1 2014 11.15 2015 11.33 2016 11.69 2017 11.78 2018 12.11 2019 13.27