Year % 2001 8.89 2002 9.61 2005 7.75 2007 7.31 2008 7.39 2009 5.02 2010 4.41 2011 3.78 2013 7.51 2015 2.58 2016 2.61 2017 2.68 2018 2.63 2021 2.92