Year	% of total fuel combustion
1985	7.5551782682512725
1986	14.531250000000002
1987	13.42182890855457
1988	8.258154059680777
1989	6.140350877192982
1990	8.164852255054434
1991	2.6548672566371674
1992	6.084243369734789
1993	3.2939189189189193
1994	3.398058252427183
1995	5.365853658536585
1996	6.805074971164935
1997	2.5912838633686692
1998	2.5821596244131455
1999	5.244755244755244
2000	2.2271714922048997
2001	5.691964285714286
2002	2.7196652719665266
2003	4.314994606256743
2004	3.676470588235295
2005	4.181818181818182
2006	5.348460291734198
2007	7.275541795665635
2008	7.4650077760497675
2009	6.199261992619927
2010	4.452296819787986
2011	6.927517639512508
2012	6.631762652705059
2013	7.234726688102894
2014	6.442731277533039