Year % of GDP 2004 24.201236285838164 2005 20.293286576731667 2006 19.497227712787772 2007 21.43636841493067 2008 21.60671315105462 2009 22.150938718186495 2010 23.188554484256578 2011 23.28531275377904 2012 22.754035513778295 2013 23.604114760943453 2014 25.40170495824104 2015 27.154044394094363 2016 28.113231255202987 2017 28.870581788080337 2018 28.507962549930642 2019 28.998986870829253 2020 31.110592495179628 2021 28.07585248338619 2022 28.047467523927732 2023 30.675664869297158