Year % 1996 3.95 2006 5.42 2007 5.4 2008 5.84 2009 5.54 2010 5.7 2011 5.66 2012 5.63 2013 5.93 2014 6.39 2015 7.02 2016 7.28 2017 7.09 2018 7.06 2019 7.87