Year	% of total fuel combustion
1960	28.564071437767844
1961	29.128240160916924
1962	29.41552329456059
1963	29.5847891708483
1964	30.206046884995043
1965	30.607348976356324
1966	31.034858700329938
1967	30.29978852405229
1968	30.84424928344747
1969	31.723301269813902
1970	32.98823454786207
1971	31.84789270617655
1972	32.46947895314236
1973	33.34389542732803
1974	33.818933679728424
1975	33.628118463240696
1976	34.23301720756076
1977	34.62053885523284
1978	34.594814969534234
1979	34.87726041027235
1980	36.197865089016155
1981	36.535240670718494
1982	36.85776296750998
1983	37.27455841113691
1984	37.2175212906594
1985	37.684641843660756
1986	37.9985014587299
1987	38.278755779031904
1988	38.4859784201547
1989	39.72426535509619
1990	43.316948102457175
1991	43.76219652831399
1992	44.811062210830066
1993	44.79137406059368
1994	45.10283414863818
1995	44.79691367011209
1996	45.54787051823401
1997	45.8117090390176
1998	46.50115353254465
1999	46.51967917334513
2000	47.075465550289756
2001	47.40626704948894
2002	47.83935857609881
2003	48.39678561897152
2004	47.7786202150976
2005	48.14885207629663
2006	48.56315521715876
2007	48.81699634247009
2008	48.43213240207324
2009	48.290774128432865
2010	48.76675081876562
2011	49.28578326239007
2012	49.46727464407452
2013	49.374732703685844
2014	49.04019652461596