Year % of GDP 1988 24.29754550261605 1989 24.494326543476355 1990 23.739230090607883 1991 25.289710719402102 1992 29.269437355092524 1993 31.012777050519507 1994 31.98412823573293 1995 33.654677588937595 1996 32.280671139217354 1997 31.374064753531428 1998 31.523496469068945 1999 31.784978254911262 2000 31.00789148967146 2001 31.705741255202362 2002 31.961813160370134 2003 31.864461653812338 2004 34.01884704365347 2005 36.16597493346021 2006 36.40685268676434 2007 37.47503583390699 2008 38.048780386748774 2009 33.675742291233114 2010 34.04424012945049 2011 35.978064402488656 2012 37.7834581640533 2013 37.01046864048681 2014 35.119844777184085 2015 33.30631986265655 2016 30.225403381037687 2017 30.505238207827112 2018 32.23933865803601 2019 30.873441842821634 2020 27.617996291749098 2021 30.472210855990213 2022 34.0398681921083 2023 29.9094327617675