Year	% of total energy use
1960	27.872272025186422
1961	30.243309235409587
1962	30.78264333372564
1963	30.289980751164457
1964	31.832583385072297
1965	30.408899370262052
1966	31.23877892193361
1967	33.75934197762264
1968	34.48371372994412
1969	42.95602262176077
1970	45.65385237753994
1971	7.565794075465277
1972	7.868540369513474
1973	7.036169350454219
1974	6.790061072651289
1975	7.014341599824218
1976	7.1185570427195435
1977	7.6223801092516945
1978	7.797243567990544
1979	7.79250309765661
1980	7.811449158054661
1981	8.041418297374618
1982	7.8553530192746335
1983	8.206830033839566
1984	7.776748056124833
1985	7.6359187887305255
1986	7.3592205044345045
1987	7.48836859403097
1988	7.387680809098766
1989	7.360474110042173
1990	2.5521256485296804
1991	2.865214409171058
1992	3.0434744308636343
1993	3.0688242376505492
1994	3.0076661379661487
1995	3.2306588280870985
1996	3.0874093991745704
1997	2.9947105875067415
1998	3.1762505238732897
1999	3.3810158333554208
2000	3.512207894834993
2001	3.48503948092561
2002	3.4442275575505734
2003	3.2693498254343796
2004	3.2558654849574724
2005	3.549861055112396
2006	3.366630628813519
2007	3.419795185925932
2008	3.835045643365265
2009	3.964466137236699
2010	3.64490397443114
2011	3.469530868108924
2012	3.368712442817322
2013	3.256677295584159
2014	3.109148819914272
2015	19.7000041519165