Many MLPs have a degree of insulation from commodity price volatility thanks to long-term deals with customers for leasing out storage facilities and pipeline deals that are based on volume of throughput rather than the price of it.

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It may also be an expensive one, as subsidies may have to be offered as an incentive - short-term contracts are not an attractive proposition when long-term assurances are needed for things such as leasing rolling stock.

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In April, Nippon Credit Bank, the most troubled of the three long-term credit banks, even allowed one of its affiliates, Crown Leasing, to go bust.

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