Year % of GNI 1987 15.223098823916835 1988 14.398884291124288 1989 15.017974710718402 1990 14.221975491547608 1991 12.842175359140656 1996 19.82235047550686 1997 21.244462456592707 1998 19.905463801225977 2002 24.650966832758762 2003 25.019182455440706 2004 27.422090452543035 2005 26.87251442088458 2006 27.96469828131366 2007 28.466410681210057 2008 28.214351986326005 2009 23.93715508896275 2010 27.563189920510847 2011 27.4084600095214 2012 26.652730166891352 2013 25.096169969395483 2014 25.06184453733406 2015 22.637634844418475 2016 25.228357161015552 2017 27.34439095696199 2018 27.723667125567225 2019 29.05273274615641 2020 28.473717374732285 2021 29.107038215693027 2022 28.39760135535903