Year % 2002 12.04 2003 10.24 2004 11.25 2005 10.1 2006 10.46 2007 10.91 2008 10.62 2009 10.36 2010 9.62 2011 9.56 2012 10.79 2013 10.57 2014 10.01 2015 11.09 2016 12.64 2017 12.04 2018 13.21 2019 12.83