Year Percent of GDP (Units) 1998 37.072 1999 39.303 2000 36.123 2001 34.303 2002 34.225 2003 32.890 2004 33.333 2005 34.345 2006 33.675 2007 32.936 2008 36.352 2009 42.398 2010 42.667 2011 39.886 2012 37.112 2013 37.329 2014 37.798 2015 37.393 2016 36.125 2017 36.478 2018 38.052 2019 37.693 2020 41.388 2021 43.162 2022 40.948 2023 39.799 2024 40.797 2025 40.049 2026 39.519 2027 38.806 2028 38.741 2029 38.694