Year	% of total merchandise exports
1964	0.30798186329027294
1965	0.5850174745479411
1966	0.3750740277686385
1967	0.8215130023640662
1968	2.1421520236920037
1969	2.5387467909099555
1970	3.3248515691263782
1971	2.220690051423482
1972	1.5722994605499758
1973	1.5321466833606547
1974	1.4333452832121274
1975	1.0704363184229664
1976	0.7626112302021807
1977	0.49363606652625464
1978	0.4619701028392519
1979	0.8395294952081689
1980	0.9334195976943889
1981	0.8960931152636971
1982	1.120424909642089
1983	0.8669448914356486
1984	0.9133576220186617
1985	1.5189449628087746
1986	1.2405743105993798
1987	1.0704049088915397
1988	1.1306327364301847
1989	1.3901333116515475
1990	1.5263059000912027
1991	1.0930933047005154
1992	1.341934399836436
1993	1.3864777089641191
1994	1.2380759750183505
1995	1.2622627917769351
1996	1.6829225534827026
1997	1.8078722784675527
1998	2.511822103615093
1999	2.9250208505252657
2000	3.5996757410845763
2001	3.6335921875245196
2002	3.648783805858354
2003	3.51919195810403
2004	3.6501714498042093
2005	3.651123740307697
2006	3.6501914123727484
2007	3.6691350810469827
2008	3.6691235975603287
2009	3.6690644333115854
2010	3.669065057186415
2011	3.6689437648706
2012	3.865785074276884
2013	3.8654987415003923
2014	3.865766683451694
2015	3.865766366735892
2016	3.865494811836541
2017	3.773809833908151
2018	3.7689963563054567
2019	3.0749910834261662
2020	3.437473392066083