Year	% of total fuel combustion
1960	41.039131864518254
1961	38.62969004893964
1962	36.95717280622941
1963	36.09981014374831
1964	38.69426751592357
1965	39.20021762785637
1966	39.443844492440604
1967	35.8920063525675
1968	34.98888065233506
1969	33.410942956926654
1970	28.7343951786483
1971	27.88065843621399
1972	27.579365079365083
1973	27.472118959107807
1974	31.240219092331774
1975	28.799514955537592
1976	27.17834631071561
1977	28.020265003897116
1978	27.287977632805223
1979	25.724508050089444
1980	23.813029076186968
1981	20.15518913676043
1982	19.951778179626277
1983	20.591212796112572
1984	21.40894819466248
1985	21.485562310030396
1986	20.62754212667054
1987	20.179457808323786
1988	21.4583747268031
1989	20.861452957522825
1990	17.12864250177683
1991	16.856906534325887
1992	16.6396833962943
1993	17.025089605734767
1994	16.70224119530416
1995	16.51283772445041
1996	15.763702416679829
1997	17.83714605663094
1998	16.63234595279582
1999	15.758659944706455
2000	17.53677064813318
2001	16.168478260869566
2002	15.233160621761657
2003	15.166071918748287
2004	15.83288263926447
2005	15.412474849094568
2006	16.249304396215916
2007	16.292458261370175
2008	17.42065201780842
2009	18.420226130653266
2010	16.89238386486093
2011	17.520215633423177
2012	17.51173708920188
2013	17.016970263116924
2014	17.686739058900955