Year % 2001 19.22309 2002 16.32871 2004 19.03916 2005 16.82314 2006 17.15013 2007 17.85825 2008 25.15745 2009 26.21338 2010 16.96782 2011 24.40216 2012 17.156 2013 25.69982 2014 25.65736 2015 26.45715 2016 28.05449 2017 22.14623 2018 17.04149 2019 16.21345 2020 18.21124 2021 18.806