Global refining margins fell 34% in the fourth quarter as a mild winter depressed demand for middle distillates, Bloomberg reports. The margin decline is reversing the trend of booming refining profits, which had previously softened the blow of low oil prices for integrated oil companies such as ExxonMobil and Shell.
Gulf Coast refining margins reached their highest point in five years in the third quarter. Tesoro reported record profits, and Valero, Phillips 66 and Marathon Petroleum saw their best quarterly results in at least three years. Those firms are set to announce their fourth quarter earnings in late January or early February.
Many refiners delayed planned maintenance in 2015 to this year amid strong margins and the spring refining strike.