Year % of GNI 1990 4.2952144240529 1991 3.93275565611571 1992 3.81854804036162 1993 3.59143925289562 1994 3.39584074242565 1995 3.25014520053049 1996 3.11926763138438 1997 2.94040101384202 1998 2.7251454106756 1999 2.54175449304092 2000 2.38850046244778 2001 2.23359953545734 2002 2.10068005592959 2003 1.97805285220536 2004 1.85619014283489 2005 1.73845113043784 2006 1.6108231587214 2007 1.50275046843524 2008 1.39939432534047 2009 1.34028411874526 2010 1.27839644083764 2011 1.20016989286272 2012 1.11586289570009 2013 1.03554586233228 2014 0.967337615610139 2015 0.901436454569714 2016 0.852057273789943 2017 0.792205274817647 2018 0.735478137066551 2019 0.685364492847128 2020 0.663393274439229 2021 0.61475905951911