Year Percent of GDP (Units) 1980 17.387 1981 17.390 1982 17.501 1983 16.908 1984 18.156 1985 20.214 1986 19.904 1987 21.918 1988 22.282 1989 23.631 1990 25.173 1991 23.153 1992 23.217 1993 23.592 1994 25.723 1995 25.711 1996 24.479 1997 26.342 1998 25.228 1999 29.934 2000 25.108 2001 30.610 2002 31.483 2003 33.157 2004 34.748 2005 36.222 2006 37.981 2007 40.658 2008 36.095 2009 36.392 2010 36.928 2011 35.402 2012 33.541 2013 32.286 2014 32.954 2015 31.067 2016 29.547 2017 29.147 2018 30.228 2019 29.230 2020 29.820 2021 30.894 2022 31.027 2023 31.781 2024 31.933 2025 31.592 2026 31.158 2027 30.768 2028 30.281 2029 29.778