Year % 2001 5.7 2002 8.02 2005 6.83 2007 6.57 2008 6.61 2009 4.23 2010 3.47 2011 2.74 2013 5.77 2015 1.36 2016 1.38 2017 1.4 2018 1.4 2021 1.72