Year	% of total electricity output
1990	6.960160999422014
1991	8.255932960786488
1992	7.575046483298074
1993	8.305123924489532
1994	9.060523474057685
1995	9.995116552433254
1996	9.760683072595405
1997	9.868168560024568
1998	10.767021709779051
1999	10.905605409566116
2000	9.558929486831202
2001	9.496150579467928
2002	9.48201947984195
2003	7.815800684236651
2004	10.020245108877068
2005	11.321573505369697
2006	10.627970450928943
2007	9.697571938298461
2008	10.873207931087501
2009	12.6978543422933
2010	15.223258952217689
2011	13.191975677207866
2012	14.965742175093416
2013	17.944810534219215
2014	20.502560503129395
2015	20.252851408387077