Year	% of total fuel combustion
1960	32.431825298498325
1961	31.75091990556955
1962	30.423517016636858
1963	29.66360856269113
1964	30.21786830381879
1965	30.722324233033614
1966	30.21482589545417
1967	29.768301638347978
1968	29.293630455144083
1969	29.396698542905302
1970	28.387728606485407
1971	28.5467504424204
1972	27.543280734404078
1973	27.284258318046163
1974	27.718701857963538
1975	26.44271728800214
1976	25.622568372693994
1977	25.80696325732561
1978	24.913454399853187
1979	24.82598421183924
1980	24.091894803912723
1981	23.425553535902903
1982	22.567156651448112
1983	22.692816035750905
1984	22.71322266742988
1985	22.097706079224444
1986	21.134077084954882
1987	21.011201420667987
1988	21.371025463373854
1989	21.339908519153802
1990	19.415316722620666
1991	17.835720869107604
1992	16.776332629664317
1993	16.493923355875722
1994	17.07437980903938
1995	17.407383830024582
1996	16.793848217595183
1997	17.112775086837896
1998	16.351958624306416
1999	15.89785124372615
2000	16.237586165713775
2001	15.674415105694727
2002	15.305448790413744
2003	15.226618715587719
2004	14.804519237254091
2005	14.318177793779991
2006	13.854604638546046
2007	14.055740134330858
2008	13.75348730848388
2009	12.36471017182424
2010	12.83956601884157
2011	13.053885880166902
2012	12.85554220608286
2013	13.063042855614642
2014	13.331032102174666