Why oil-price rallies soon falter

Opec, the oil exporters’ cartel, has never been very good at sticking to deals to rein in output. They recently agreed to cut production to mop up a glut and shore up prices, but it turns out they aren’t doing too well this time round either. According to the International Energy Agency, some producers are “showing signs of weakening their resolve”.

In July, the compliance rate among Opec members was just 75%; overall production actually rose. Expect the cheating to continue, Tariq Zahir of Tyche Capital Advisors told Barron’s.com. Some countries could even pull [...]