The past year was not good for OPEC. The global oil glut slashed oil prices by more than 50%, and brought into question the traditional role of the Organisation as a key global market mover. However, the downward trend had already begun took place in the beginning of the decade when the US shale revolution, helped by the $100+ oil prices, started to affect global oil markets.

Read more: http://tinyurl.com/qys3uts