Year	% of total electricity output
1990	40.1918047079337
1991	29.3162393162393
1992	24.7497725204732
1993	18.8976377952756
1994	20.7957957957958
1995	16.1837455830389
1996	26.5319865319865
1997	23.8845144356955
1998	24.9528598365808
1999	29.1358024691358
2000	27.2948328267477
2001	21.631000578369
2002	18.7535734705546
2003	18.6575654152446
2004	20.0834326579261
2005	18.9591078066914
2006	16.8803418803419
2007	22.1703011422638
2008	26.4064660214825
2009	22.5718964282059
2010	15.0389342339807
2011	18.8586102317756
2012	20.1104938568388
2013	20.5091057124726
2014	11.6734851101134
2015	14.0947086721567