Year Percent of GDP (Units) 1996 18.632 1997 18.715 1998 18.996 1999 17.975 2000 17.325 2001 19.328 2002 19.686 2003 16.669 2004 17.736 2005 18.288 2006 18.972 2007 21.960 2008 23.116 2009 20.797 2010 21.523 2011 22.574 2012 22.035 2013 22.750 2014 23.235 2015 22.788 2016 23.179 2017 24.181 2018 25.488 2019 24.572 2020 24.581 2021 22.479 2022 22.484 2023 22.768 2024 23.058 2025 23.153 2026 23.194 2027 23.194 2028 23.194 2029 23.194