Year % of GNI 1990 15.3675161447174 1991 12.6519703041547 1992 9.24030149787194 1993 6.55827464183503 1994 13.5776599942035 1995 17.0670188159111 1996 16.8602208172925 1997 16.8799516026475 1998 16.8976763567019 1999 16.9914340773829 2000 17.5520590836342 2001 17.1934916861239 2002 16.0550175200413 2003 17.561497298715 2004 18.3663601977456 2005 18.4832376164252 2006 20.6356540576191 2007 21.7547991678553 2008 20.6628789655271 2009 15.4583288074034 2010 17.4031954628296 2011 17.5426972516073 2012 17.1666474542492 2013 16.913627164643 2014 17.184419810534 2015 17.4759878619669 2016 17.3126087782218 2017 18.2827731028946 2018 18.0683904804151 2019 19.6581804324538 2020 19.6410057135243 2021 19.753713446822