The index provides a weighted average of rates across key Asia-Europe, transpacific and transatlantic trade lanes.
The index had more than doubled last year following the May 2009 low point. Drewry's Intra-Asia Freight Rate Index has lost 18 per cent of its value since March.
"Our research shows that freight rate volatility has been increasing over recent years, with more violent frequencies of oscillation," said Container Freight Rate Insight editor Martin Dixon, reported American Shipper. "Cargo owners need to accept that volatility is now a long-term feature of more turbulent times and plan accordingly."