Year % 1995 8.82 1997 12.75 2002 8.04 2006 5.32 2007 6.14 2008 5.31 2009 4.61 2010 6.09 2011 5.02 2012 5.17 2013 5.9 2014 5.34 2015 5.05 2016 5.67 2017 4.02 2018 3.58 2019 20.91 2020 3.12 2021 3.01