Year % of GNI 1977 32.353021795223164 1978 26.220286748163307 1981 23.028516950945072 1982 24.30462081539752 1983 25.678856283261197 1984 23.55783663772594 1985 21.124239020355656 1986 16.83468463133843 1987 20.298221684379087 1988 16.51410229651292 1989 21.122417478592507 1991 30.94130055535758 1996 30.186059599203436 1998 24.81090946889913 2014 25.790501972876566 2015 19.44988172121584 2018 26.55169152741899 2019 24.89434928694668 2020 15.922417887576696 2021 20.056202382010024