ince crude oil and commodity prices bottomed in January 2016, optimism has generally reigned. There was a period of concern at the end of 2016 because of growing crude oil inventories in storage tanks and vessels used as "floating storage." Crude oil prices eased for a couple of months, dropping from the low $50s to the low $40s.

Last November, OPEC and several non-OPEC producers agreed to cut production 1.8 million...