Year % 1996 8.85 1997 9.5 2000 7.63 2001 7.91 2002 8.8 2008 2.75 2009 2.79 2010 2.63 2011 2.34 2012 2.47 2013 2.96 2014 2.39 2015 1.97 2016 1.82 2017 1.51 2018 1.65 2019 2.82 2020 1.76 2021 2.27