Year	PPP $ per kg of oil equivalent
1990	9.952228688155818
1991	10.57274646905784
1992	9.803573428747574
1993	9.859641610000573
1994	11.782273279600767
1995	11.515309976297326
1996	11.66941111337004
1997	12.398829734009512
1998	12.196961267680232
1999	11.572716374476034
2000	11.558606319398763
2001	11.24512137307828
2002	9.436621759300028
2003	8.369288339615984
2004	7.45648583273323
2005	6.835078356492613
2006	6.08821681367913
2007	5.951488819976139
2008	5.33730609127709
2009	4.915293503824483
2010	4.742872473157871
2011	6.437753003957217
2012	7.4455561388545854
2013	5.23835722994698
2014	5.790044020525387