Year	% of total fuel combustion
1990	3.0241935483870925
1991	7.785299806576402
1992	6.572769953051644
1993	6.707317073170731
1994	10.074626865671645
1995	5.934718100890208
1996	4.583333333333334
1997	3.481012658227848
1998	3.6585365853658542
1999	3.4129692832764498
2000	6.432748538011698
2001	6.0693641618497125
2002	8.934707903780069
2003	10.397553516819569
2004	10.115606936416183
2005	10.169491525423728
2006	9.638554216867467
2007	8.75
2008	8.159392789373815
2009	9.367681498829041
2010	16.54320987654321
2011	14.989293361884371
2012	14.338235294117649
2013	14.312977099236642
2014	0.3831417624521055