Year	% of total reserves
1973	0
1974	0
1975	0
1976	0.020653622507155345
1977	0.04413368155447492
1978	0.06390182468373004
1979	0.03917084193274495
1980	0.0401314673688081
1981	0.06020533213412693
1982	0.10587995956240183
1983	0.12365484819482023
1984	0.1626570666589638
1985	0.19558112726297305
1986	0.1728943148084057
1987	22.271179885887925
1988	52.65037105595317
1989	32.18086455392366
1990	52.96388331361301
1991	76.33177975936592
1992	89.59471614500558
1993	83.24782255778021
1994	66.2285324850639
1995	55.624241349821226
1996	124.54123835767778
1997	125.73660379466915
1998	126.35676213694111
1999	159.21266871917092
2000	183.6854185342415
2001	110.59953278235591
2002	117.18938062352177
2003	119.85558088503556
2004	109.64830569036883
2005	88.61501341424744
2006	61.02540723693431
2007	28.163905484381967
2008	26.974395040537352
2009	19.738811345066505
2010	19.495855331126194
2011	16.612306204814406
2012	13.39415733820633
2013	0.35545653525697457
2014	1.9867619267009882
2015	2.1538030319630033
2016	1.8638986289813912
2017	1.8570887463800374
2018	1.8547848855650182
2019	1.1319700262294068
2020	0.886670145628556