Year	% of merchandise exports
1970	16.90534356194353
1971	16.413541858285992
1972	16.706587016008605
1973	12.949361175518748
1974	9.74918407883535
1975	12.954605389779386
1976	15.617178976851548
1977	12.174592787290266
1978	10.932811030961666
1979	12.191488748007226
1981	0.14372278012587486
1988	0.012785455382365146
1989	0.10410375396724722
1990	0.11696528040248708
1991	0.012963824039983128
1992	0.0025479209980920356
1993	0.007706028518337463
1995	0.04593617059180634
1996	0.0965993718117905
1997	0.07748703258045615