Year % 2001 13.651922878647282 2002 16.758962068534146 2003 17.337611782366917 2004 17.3791192732543 2005 19.282331754818916 2006 18.604401733236088 2007 20.511181879922585 2008 17.90791546019208 2009 19.54381151884784 2010 20.23541452515861 2011 20.127068718504162 2012 17.984122630312413 2013 24.17750462865412 2014 20.41900023209481 2015 23.02489020011642 2016 16.550455579475116 2017 14.585444334398042 2018 18.056890488606776 2019 17.375474889848586 2020 16.2821548578034 2021 16.698845258639796 2022 13.678376769924746 2023 11.187903407778798