Year	% of total merchandise exports
1977	1.1372125840458205
1979	1.2082444918265813
1980	3.9047704932816307
1981	9.51048951048951
1982	2.849986206544314
1983	11.240250461309683
1984	9.68161517284492
1985	19.96494138156271
1988	27.959212498561588
1990	0.06670563009893395
1991	5.312557496663165
1992	0.00835046595520125
1993	3.7346110189390993
1994	6.289709899465895
1995	10.61410447028607
1996	5.786525157741706
1997	6.713479479492432
1998	3.5000445651670398
1999	1.7095161003055885
2000	1.2989639494672576
2001	19.520489609472826
2002	17.092626373171353
2003	1.3951868420103564
2004	0.37692675546490584
2005	0.30004993302534855
2006	0.7758477789176191
2007	0.11174926867252712
2008	1.4276191287505624
2009	1.2761459988147201
2010	2.9976205224574297
2011	1.286398070750925
2012	4.558451173700889
2013	6.813952244304493
2014	20.36627455225289
2015	15.608447595548197
2016	18.26210172211496
2017	17.467943192980705
2018	4.628281494775025
2019	4.144250783493782
2020	0.04883016211919131