Year	% of energy use
1960	51.368302589231064
1961	52.004779138368775
1962	59.391004704699355
1963	62.87931545360912
1964	63.62804008394103
1965	63.835280978397336
1966	64.7793403639853
1967	63.204170182668726
1968	55.59551143000081
1969	48.302035841750964
1970	41.199833848798
1971	26.58980700906574
1972	18.1735116308131
1973	8.447405297990842
1974	-9.411307754854782
1975	-20.85976142388518
1976	-16.81582120166956
1977	-20.336656391084976
1978	-7.601432291514433
1979	-7.603100643989609
1980	-11.58471610042613
1981	-9.745357305513389
1982	-6.054765916745922
1983	-9.282171616947876
1984	-5.19920981921939
1985	-9.39225188214419
1986	0.9476766874217897
1987	3.731590376075803
1988	13.34624963840461
1989	7.285142078987278
1990	7.824583928417049
1991	2.8600928121634577
1992	1.4088618017416403
1993	0.5727357030628795
1994	4.262033898778855
1995	9.467619178979831
1996	3.973889852400098
1997	11.88111789686123
1998	15.951874803472602
1999	19.96259018406733
2000	23.27991170665868
2001	20.50291588036227
2002	22.626859584510687
2003	27.5106466016705
2004	17.5940246886786
2005	23.18578826321706
2006	23.73069539763833
2007	23.7228029981417
2008	16.412336322562858
2009	19.19710595594353
2010	16.30284920347555
2011	16.77561686436142
2012	16.852487731514163
2013	10.384686264115823
2014	19.76928935098444
2015	35.02100765364129