Year	% of total fuel combustion
1960	32.99969669396421
1961	32.79728533490705
1962	30.66087414428647
1963	28.485864877815047
1964	30.016762452107283
1965	30.3830760434534
1966	30.58350100603622
1967	30.68281938325991
1968	30.055193176116408
1969	28.632712668857245
1970	33.49976224441274
1971	33.34639191412678
1972	31.908171861836564
1973	31.61264236134511
1974	32.85744878292526
1975	32.287165491623085
1976	30.54666951020118
1977	31.725283454899973
1978	31.323447118074988
1979	32.36446766819072
1980	34.1221794166208
1981	34.74375087278313
1982	35.4118781048417
1983	32.82987042858238
1984	33.68327665237321
1985	33.06830502349115
1986	35.237960540272965
1987	35.521607486925404
1988	39.27699071812408
1989	40.16124624214265
1990	40.8560579910252
1991	38.793216774023925
1992	40.61071736106511
1993	40.37143772014089
1994	41.923716882119535
1995	40.182229560325325
1996	38.547744208884524
1997	41.07498341074983
1998	42.43409172986638
1999	40.6393830078368
2000	41.40813672673231
2001	42.02463202162812
2002	42.48620772367475
2003	42.46333274430111
2004	42.94460641399417
2005	42.57828872522604
2006	40.58140249523692
2007	43.11926605504588
2008	42.303244263193136
2009	42.621614844533596
2010	41.727465285949634
2011	42.77398127056441
2012	41.502178928479886
2013	41.58104289750835
2014	45.84737764594849