Year Percent of GDP (Units) 2000 44.909 2001 43.841 2002 45.463 2003 49.376 2004 46.738 2005 40.359 2006 34.940 2007 31.870 2008 28.036 2009 28.272 2010 25.156 2011 23.071 2012 20.657 2013 19.949 2014 20.591 2015 23.965 2016 24.336 2017 25.234 2018 26.024 2019 26.957 2020 34.919 2021 36.110 2022 33.924 2023 32.086 2024 33.002 2025 33.293 2026 33.199 2027 32.639 2028 32.128 2029 31.644