Year	PPP $ per kg of oil equivalent
1990	9.627937932363919
1991	8.69351521242061
1992	8.809186210867685
1993	10.83511418961277
1994	11.311755552427348
1995	10.782448285751638
1996	11.25219145161533
1997	11.335648267703684
1998	11.373171545581178
1999	10.60452507596579
2000	10.846545322867394
2001	10.379847315563536
2002	11.31007087581109
2003	10.769468371547136
2004	10.534763535006942
2005	10.77136413152
2006	10.700603703143807
2007	11.605778518205039
2008	11.627088766058252
2009	10.950416697993624
2010	12.30752225893466
2011	12.982919856324534
2012	14.282591284843203
2013	11.22191264279663