Year	% of energy use
1960	42.82320186437232
1961	46.52076174782813
1962	49.88809293507189
1963	55.827843460325965
1964	55.3895971525703
1965	56.24364949162016
1966	57.0435518110176
1967	61.14579237132275
1968	65.93056920728189
1969	68.35267327832118
1970	67.33521124725294
1971	69.97681990842372
1972	72.01160767116657
1973	75.47788020596428
1974	75.73489133927627
1975	73.5881130784013
1976	76.65612789276062
1977	74.24801311120008
1978	75.1929957499326
1979	75.07825237920935
1980	72.57127720577763
1981	65.84710600988838
1982	65.22688035342871
1983	61.0749972499407
1984	56.218851460380414
1985	54.215464401459734
1986	51.761775203293425
1987	51.09265499899958
1988	50.548870842996195
1989	50.29522307284897
1990	50.0589872881943
1991	49.94910291278305
1992	48.35533367512126
1993	46.56741698473022
1994	45.61438580954537
1995	46.06458863199098
1996	47.38343844519854
1997	46.98181335832587
1998	49.80776522992681
1999	49.03473187179501
2000	48.13281961455196
2001	49.32858783490505
2002	48.65845485499833
2003	48.94658936330669
2004	49.2438301165299
2005	49.38184501434898
2006	48.8981233363882
2007	49.039075402134436
2008	48.51809178880754
2009	49.24531093014658
2010	48.16346592374847
2011	46.06021462613417
2012	46.79923106658178
2013	46.352875017262285
2014	43.48527185200152
2015	44.11016596524359