Year	% of total fuel combustion
1971	34.99241969163878
1972	35.816741597088416
1973	35.93719713122699
1974	36.09032815591386
1975	36.767824012721974
1976	36.40546339853098
1977	35.60308224563611
1978	35.425514312503445
1979	35.82955733705124
1980	35.43592074474353
1981	36.72373111099955
1982	36.17488322962913
1983	34.80262826222125
1984	34.67065769237129
1985	34.09549866458211
1986	34.18739596459296
1987	33.364671471847906
1988	33.22527174311657
1989	33.989675832582606
1990	35.55852959574066
1991	35.709779179810724
1992	35.80437296910282
1993	36.36803418573712
1994	35.844806641020455
1995	36.3482776183555
1996	36.34974732636032
1997	35.98924207543828
1998	35.640732265446225
1999	35.353546095519654
2000	34.309793369548665
2001	34.54395503696011
2002	34.62672904800651
2003	34.59530156448118
2004	35.26440935894997
2005	35.2974430738719
2006	35.6191384803701
2007	35.91117983824027
2008	36.3534088986635
2009	36.47111889871012
2010	36.608847544379906
2011	37.43782546762253
2012	37.797468926213405
2013	37.532266773174754
2014	37.38420326794082
