Year	% of total electricity output
1990	67.71988190192369
1991	67.55812852394396
1992	67.58901438763674
1993	68.95846499789658
1994	67.87664228340233
1995	67.6267018370351
1996	67.33984895962118
1997	66.26171973009491
1998	63.848075728187695
1999	62.86064785907973
2000	62.812114891573266
2001	59.405192910778204
2002	59.981187502866675
2003	58.84491951321876
2004	59.01786895070023
2005	59.92190616296506
2006	60.330973272477884
2007	59.72494017604749
2008	58.794421563937576
2009	59.30563564980951
2010	58.34031034833834
2011	59.299336162661795
2012	56.60351148935131
2013	54.839090541963955
2014	54.615894897974925
2015	53.2443890816753