Year Percent of GDP (Units) 1996 39.104 1997 34.882 1998 27.629 1999 41.128 2000 42.858 2001 37.463 2002 28.681 2003 29.715 2004 30.987 2005 33.697 2006 40.027 2007 42.440 2008 48.431 2009 37.110 2010 42.789 2011 45.483 2012 41.340 2013 36.746 2014 30.736 2015 24.134 2016 17.523 2017 17.516 2018 22.866 2019 21.179 2020 21.345 2021 23.307 2022 23.222 2023 20.019 2024 20.833 2025 20.105 2026 19.356 2027 18.441 2028 17.907 2029 16.298