Investors who piled cash into fuel-efficient containerships have reasons to be anxious.

The hefty premiums they had banked on are being eroded rapidly as cheap oil threatens to put what has been a two-tier market onto a single track.

The market is already heading in that direction as the gap narrows for older and modern boxship designs.

Charter rates for feeders up to the larger wide-beam ecoships are losing their shine and owners are having to lower their rates or pitch their vessels using other factors.

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