Year Percent of GDP (Units) 1988 24.886 1989 25.676 1990 25.816 1991 27.272 1992 26.689 1993 26.194 1994 26.208 1995 24.980 1996 24.364 1997 25.231 1998 26.034 1999 25.850 2000 26.086 2001 28.276 2002 29.115 2003 29.942 2004 28.450 2005 26.876 2006 26.910 2007 26.945 2008 29.293 2009 28.543 2010 27.985 2011 27.641 2012 27.364 2013 26.600 2014 26.220 2015 27.059 2016 27.233 2017 26.232 2018 26.328 2019 26.846 2020 31.019 2021 28.998 2022 29.008 2023 28.779 2024 27.958 2025 27.833 2026 27.543 2027 27.338 2028 27.186 2029 26.998