Year Percent of GDP (Units) 1991 38.985 1992 41.454 1993 45.095 1994 47.537 1995 54.902 1996 57.794 1997 58.867 1998 59.535 1999 60.387 2000 59.340 2001 58.193 2002 59.946 2003 63.538 2004 65.201 2005 67.546 2006 66.887 2007 64.158 2008 65.682 2009 73.157 2010 81.995 2011 79.417 2012 80.745 2013 78.322 2014 75.279 2015 71.947 2016 68.955 2017 65.204 2018 61.914 2019 59.580 2020 68.773 2021 68.986 2022 66.077 2023 64.278 2024 63.745 2025 62.301 2026 61.000 2027 59.848 2028 58.717 2029 57.700