Year % of GNI 1990 15.3879296086367 1991 12.2148981180305 1992 28.8656582660213 1993 23.0599923207049 1994 22.1033953953351 1995 21.0586248335068 1996 20.5157170670949 1997 19.4125707618991 1998 18.5192393280778 1999 18.3427288341249 2000 18.1181426153028 2001 18.6042612839548 2002 19.10131156533 2003 20.7287622260493 2004 20.7280359900889 2005 20.3499612271272 2006 19.0264017595799 2007 22.2227662599506 2008 20.4974079046131 2009 20.4131841851206 2010 20.5622645192115 2011 19.3115393216168 2012 19.8622610693133 2013 18.6139084501084 2014 18.4089750458021 2015 17.9198489093392 2016 17.492379621615 2017 16.2935259371914 2018 17.0803902014185 2019 17.4428589059829 2020 16.8904486642327 2021 16.6023767441264