Year	% of total electricity output
1990	17.2162480324855
1991	17.9703907618143
1992	12.509253350351
1993	16.1632537522758
1994	18.0606829001504
1995	14.7201623227614
1996	23.7908459031523
1997	19.5461730823116
1998	19.0736948787954
1999	13.2668082026069
2000	15.6137261736096
2001	21.1535738650259
2002	13.8306164215124
2003	21.67904458772
2004	18.1346962971531
2005	14.6013923197844
2006	17.6428199281418
2007	19.3093006536597
2008	19.9830856202046
2009	25.3812498072766
2010	32.7755430410298
2011	30.0216442049442
2012	29.5847480115125
2013	39.5835776084137
2014	40.1052558838185
2015	34.949890565603