Year	% of total energy
1960	54.994828279902826
1961	54.838206026885075
1962	50.13486057208687
1963	46.89303911469657
1964	44.91927730462725
1965	42.5090200559124
1966	39.177557455789305
1967	38.02604564636631
1968	36.11291959246811
1969	34.08936710412753
1970	32.79012777077308
1971	44.65478444999968
1972	43.708396305711126
1973	42.4195282102036
1974	41.756041266708934
1975	40.167303549748716
1976	39.11884570276067
1977	37.518481939877155
1978	36.09593058100363
1979	35.48206871885714
1980	35.21845380665896
1981	35.079344143386926
1982	34.31091915990808
1983	34.06897742963599
1984	33.22749355548354
1985	32.656222166777376
1986	32.03568474094613
1987	31.269545771335324
1988	30.475445223428753
1989	30.15593013358588
1990	17.55508427710887
1991	17.709492814479017
1992	18.221899298411422
1993	18.254647335092308
1994	18.546737414113995
1995	18.155013584506875
1996	18.028949891355158
1997	17.992038754156756
1998	18.094013694916896
1999	17.887730327950965
2000	17.507564113491014
2001	17.041614177685954
2002	16.68613745508634
2003	15.755532807342744
2004	14.771875825772883
2005	14.088701895159065
2006	13.548969334498189
2007	12.915716270046067
2008	12.491086773939209
2009	12.22962417043662
2010	11.534789132794469
2011	11.042382747533557
2012	10.711133106022563
2013	10.583148335705243
2014	10.324070624841683
2015	3.1460913773944923