“Quite frankly we didn’t expect the commodity price rout to be so dramatic and in all likelihood the next six months are going to be even tougher,” Mark Cutifani, the company’s chief executive, said at an investors’ conference on Tuesday. “We have pulled costs out of the business, but we need to do more because prices continue to deteriorate.”

China looms large in the commodities equation.

Between 2000 and last year, companies invested hundreds of billions of dollars to expand their production capacity to satisfy China in a period of rapid economic expansion. Much of the corporate growth was fueled by debt.

But the situation has proved unsustainable as demand has waned. Chinese copper imports are down nearly 3 percent from last year, while imports of steel products are down by more than 12 percent. The country’s crude oil and iron ore imports are still up, but by rates that are slowing from previous years.

The economy’s slowing growth rate is adding to the uncertainty. China reported on Tuesday that exports, the country’s engine of growth, slipped 6.8 percent in November, compared with the same month a year ago. Imports were also weak, although the rate of decline was lower than in the previous month.

The weakening Chinese demand is hurting prices while production is overwhelming markets.

Even with prices falling rapidly, American oil production has only declined to 9.2 million barrels a day, from a record high of 9.6 million barrels a day in June. Momentum in drilling and production have been building over the last three years. Gulf of Mexico offshore production has been steadily increasing since the federal drilling moratorium that followed the 2010 BP oil spill.

Many international oil projects have been canceled and production should fall more rapidly next year. But it probably won’t be quickly enough to stabilize prices. That is because companies are getting more production out of their investments as efficiency has improved. And some need to keep producing to keep up with their debt payments.

The commodity fallout has been global.

The Swiss company Glencore is scrambling to reduce its $30 billion debt by a third before the end of 2016 by slashing its copper-mining operations in Zambia and the Democratic Republic of Congo and selling much of its agricultural business. Kinder Morgan, the North American pipeline company, cut its dividend on Tuesday afternoon, prompting a sell-off in the stock after hours.