Year	% of total energy use
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0.009188688653037966
1987	0.054879267291251387
1988	0.07869071127659581
1989	0.04919261195609273
1990	1.797314140272288
1991	1.7305407997900701
1992	1.5552107009898553
1993	1.5834043265075264
1994	1.463250478958638
1995	1.3801235192429835
1996	1.3520385761631795
1997	1.3625002107018813
1998	1.3756792221956502
1999	1.4026550664170019
2000	1.396804763814151
2001	1.4255677890489775
2002	1.3741163933619494
2003	1.3333470833794034
2004	1.1549546653320661
2005	1.0798321751934847
2006	1.4515530006625712
2007	1.4597101360014548
2008	1.631904252569645
2009	1.676249316336235
2010	1.8219089280646195
2011	1.91322616245433
2012	1.8487087886399696
2013	1.9357937977351511
2014	1.917725857958456