Year	% of total energy use
1971	0.8993426927718219
1972	0.6568500942664303
1973	0.4379029967143875
1974	0.8761405846388534
1975	1.0509025284689109
1976	0.839656018519708
1977	1.5823999167157938
1978	1.7304739211014033
1979	0.3696230478293129
1980	0.36808972919273686
1981	0.36075697145184804
1982	0.5137293164214174
1983	0.17551001556389303
1984	0.3376929618710752
1985	0.6627196855934514
1986	0.6072707102447201
1987	0.573744516903781
1988	0.5620030559346095
1989	0.681463687244034
1990	1.4040197428833794
1991	1.4868435778369988
1992	1.8723152409953179
1993	1.466807615492414
1994	1.115042285890927
1995	1.9303097322532203
1996	1.7709467450567284
1997	1.5210433114652755
1998	1.3095171406580386
1999	1.0508413478016885
2000	1.0849566691428962
2001	0.8118649106469107
2002	1.1179510685552938
2003	1.4083015128361127
2004	0.9382912187954845
2005	0.866020900135132
2006	0.9321267367896248
2007	0.9956301144730277
2008	1.5821923695972198
2009	1.5600989718304525
2010	1.2005007962470937
2011	2.093474439923311
2012	2.254340508703496
2013	2.157921007891852
2014	2.406003709493863