Volatile market conditions

Saudi Arabia wants Opec to keep cutting, despite the steady tightening of the market. It's a risky strategy

Get ready for the oil-market rollercoaster of 2018. Having paused for breath near $70 a barrel, the oil price now seeks direction—but the arrows point different ways. Eighty-buck Brent now looks distinctly plausible. But so, if less compellingly, does $40. The market is at a crux. Every bullish cylinder is now firing at once. The global economy is roaring ahead. Oil demand is surging. Geopolitical tensions are building. Crude and products inventories are shrinking. Speculators are hoovering up paper barrels. Opec is jawboning. Even the weather in big consumer countries has been cooler than normal. Lingering in the background are two potentially bearish forces: a big supply reaction, especial