A Lesson from Physics on Oil Prices: Revisiting the Negative WTI Price Episode
While the episode of negative WTI price is still being actively debated, its proper root cause is yet to be determined. This Comment contributes to the discussion and studies the event by modifying the theory of storage for an oil market with rigid operational infrastructure, where short-term supply and demand are price inelastic. We found that such pricing anomaly can be well characterized by a simple concept borrowed from the physics of extreme events.
The future prices are modelled as a financial derivative of the storage capacity. During normal market conditions, the spread between nearby futures contract is mostly determined by the carry trade and the cost of storage. However, if either inventory or the storage capacity is no longer available, the carry trade breaks down as the futures trader is unable to make or take the delivery of physical barrels. These events are akin to defaults in financial markets and prices leading to them are characterized by the financial squeeze.
We calibrate the model to inventory data at Cushing, Oklahoma and conclude that only a small fraction of the abnormal price move could be attributed to constraints on the storage capacity. The rest of the move was caused by the financial squeeze on long futures positions held against over-the-counter products. We detail the behavior of main market participants that led to negative prices. The Comment also points to several shortcomings of the recent CFTC report on this topic and suggests additional areas where a more granular look at the data could be helpful.