Year % of GNI 1987 14.032366479388116 1988 13.24016985179397 1989 14.047261215406543 1990 11.623018930531124 1991 9.893786583527492 1996 16.143043811313895 1997 17.351660153644314 1998 18.69554057402986 2001 20.304791814578454 2002 22.676648537329275 2003 23.06661473863662 2004 25.09886824631613 2005 24.66545910463635 2006 26.849196671356317 2007 27.25234617756775 2008 27.968071824751043 2009 24.38379608788609 2010 27.02970271328094 2011 28.2057853760165 2012 28.84496170045225 2013 27.678368085735798 2014 28.088674146551142 2015 26.541183015321668 2016 27.56831174884725 2017 28.691858810762376 2018 28.72720644688564 2019 30.14112597891492 2020 29.80636736225229 2021 29.280415806996245