Year Percent of GDP (Units) 1997 72.194 1998 71.184 1999 68.183 2000 63.769 2001 60.613 2002 64.097 2003 60.245 2004 57.474 2005 58.203 2006 56.688 2007 53.550 2008 55.140 2009 59.666 2010 57.720 2011 59.413 2012 62.144 2013 70.391 2014 71.992 2015 73.716 2016 73.324 2017 71.895 2018 69.472 2019 67.368 2020 75.772 2021 75.218 2022 65.546 2023 60.019 2024 58.022 2025 57.024 2026 56.473 2027 55.827 2028 54.734 2029 55.320