OPEC – What Difference has it Made?
The main purpose of this paper is to review the evolution of OPEC models and to link this evolution to some key events in the oil market. Our main conclusion is that OPEC’s pricing power varies over time. There are many instances in which OPEC can lose the power to limit oil price movements – either up or down. Such changes in pricing power are brought about by market conditions and can occur both in weak and tight market conditions. Because of OPEC’s varying conduct, there is no single model that fits its behaviour and hence analysts have been forced to choose from a wide range of models to explain certain episodes. The empirical literature has not been successful in distinguishing between the various competing models, as these models offer very similar predictions. This paper is forthcoming in the Annual Review of Resource Economics.