High levels of borrowing at many energy-sector firms may be magnifying a historic slump in the oil markets, according to a new report from the Bank for International Settlements.

This has created a vicious cycle in which companies are forced to keep up production to meet short-term debt obligations even as prices fall, exacerbating the downturn, the BIS says in its latest quarterly review of world financial conditions. The BIS, based in Basel, Switzerland, is an international organization of central banks.

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