Year	% of energy use
1990	39.64412612111948
1991	30.04777710512897
1992	31.481674107477097
1993	29.80861362237809
1994	35.878152479086836
1995	35.960577270532404
1996	36.177868410408514
1997	42.29036873168439
1998	44.96491714571364
1999	48.89924542350521
2000	49.17039852089192
2001	47.05716724755126
2002	49.697757709930926
2003	51.820197328908925
2004	50.58247578449813
2005	51.18285297409351
2006	48.41717695966749
2007	51.37337553105564
2008	51.16507192030638
2009	47.906330660837135
2010	45.10363221960264
2011	49.76603286606846
2012	51.11390986537299
2013	47.411315659339856
2014	45.85969270444382