Year % of GNI 2001 15.5908885815205 2002 19.9685164479125 2003 19.0711696500587 2004 17.9711654851034 2005 23.416950400514 2006 23.5776145663234 2007 21.5902535120367 2008 31.9865522857417 2009 23.6480473040373 2010 32.9323714138503 2011 35.4117308759163 2012 38.0670368045129 2013 38.5205775994902 2014 37.5332692980882 2015 34.8058498618028 2016 35.8991419197399 2017 34.3596666130886 2018 30.3014784202048 2019 30.7925534734339 2020 31.1444467937863 2021 24.0484937317743