When Frank Loesser penned “Slow Boat to China” he was actually romanticising a common poker player’s wish to be trapped with a cash-rich good loser for a long time. Container shipping lines are currently slowing their vessels to and from China. Their shareholders have already been big losers yet the end of the voyage is not in sight.

The share prices of container shipping companies rallied sharply early this year on hopes the worst of the industry’s downturn was over. But a rash of gloomy updates has put paid to that. Container losses wiped out first-quarter profits at AP M?ller-Maersk, the industry leader reported last month. Asian shipping lines such as Neptune Orient Lines, Evergreen Marine and Hanjin Shipping have seen share price gains of at least a quarter, and as much as 60 per cent, reversed. And all in spite of a doubling of freight rates in March as concerns over capacity took effect.

Demand is less of a problem than supply. Container volumes rose 7 per cent in 2011. Barclays forecasts 8 per cent growth this year, even if Maersk says global demand in the first quarter is just 1.3 per cent up on the same period last year. Some ships ordered in the boom have yet to be delivered. Cost-cutting measures, including slower, more fuel-efficient speeds, have staunched the red ink, but they have not fully offset overcapacity and high oil prices. Higher freight rates are critical to just breaking even, but the latest market despondency has been worsened by fears that rates will not hold their gains – forward prices are already slightly softer – if the current industry detente breaks.