Year % of GDP 2005 18.823283563147086 2006 19.380725626786866 2007 19.380414495387676 2008 18.57965764609569 2009 18.301035459213143 2010 17.130570570836724 2011 18.694145538196025 2012 20.274092482882697 2013 20.687453691542547 2014 20.371229229790966 2015 20.960091682192203 2016 21.488253200203356 2017 22.627123974930633 2018 23.36716792330652 2019 23.78671650151446 2020 23.9472430412931 2021 24.459372702055248 2022 24.579573458949156 2023 23.88276779525439