Year	% of total energy use
1960	39.33606661600113
1961	41.45994501401813
1962	43.76554285388291
1963	42.719431785882726
1964	44.453340162631406
1965	44.9784772619181
1966	41.215240730566535
1967	43.01662121374641
1968	44.438076076591045
1969	40.15141620258509
1970	37.531719720911
1971	40.8148272603518
1972	42.077511553084676
1973	43.85189130884616
1974	46.16342433393253
1975	45.446494150242856
1976	44.16997355658205
1977	37.73118674022326
1978	39.21814543752426
1979	41.929008754160044
1980	39.18172319705104
1981	44.10888220836234
1982	45.356002571208556
1983	49.72235536827944
1984	47.08476071482189
1985	44.03422781374445
1986	39.51494915438162
1987	42.017463961236444
1988	46.16734028646854
1989	48.33177898008098
1990	39.4753622131733
1991	39.13073511521997
1992	38.644177099421086
1993	36.84939396216448
1994	37.92657031014102
1995	37.93937998310454
1996	38.811654017518585
1997	37.03932771277296
1998	37.371900325564496
1999	35.62609852171567
2000	36.07404941760706
2001	35.89868809232886
2002	37.643053129654156
2003	32.73450098156605
2004	34.958784626993825
2005	35.54054781027005
2006	33.953273077356506
2007	34.38676169791304
2008	29.964513263227037
2009	28.73333648780684
2010	27.803623225145323
2011	32.183221747139825
2012	31.888495732176352
2013	29.171739177794088
2014	32.27579345510165
2015	31.31793142254392