Year Percent of GDP (Units) 1997 14.423 1998 13.868 1999 12.400 2000 12.047 2001 12.138 2002 12.461 2003 11.414 2004 12.470 2005 12.571 2006 13.427 2007 14.454 2008 14.380 2009 13.384 2010 13.128 2011 10.308 2012 13.865 2013 14.236 2014 13.645 2015 14.460 2016 14.602 2017 14.835 2018 14.656 2019 14.978 2020 14.951 2021 15.694 2022 15.004 2023 16.022 2024 16.452 2025 16.966 2026 17.539 2027 17.996 2028 18.155 2029 18.539