According to the report from Sea‑Intelligence, a leading provider of research, data, and advisory services in the global supply chain industry, specializing in container shipping, weekly capacity on individual liner services has become significantly more volatile and unpredictable on major East-West trade routes since the pandemic. This instability has resulted in lumpier cargo flows into ports, particularly affecting Asia-Europe lanes and contributing to ongoing port congestion.

The report highlighted that ideally, liner services should provide consistent weekly capacity. However, variations in vessel sizes, blank sailings, and schedule delays led to frequent fluctuations in weekly TEU capacity.

Sea-Intelligence measured the volatility using the standard deviation of vessel capacity over a 52-week rolling window, removing seasonal effects. On the Asia-North Europe route, average volatility rose from 12.3% during 2011 to 2019 to 29.6% between 2021 and 2025, more than doubling. A similar pattern was observed on Asia-Mediterranean lanes.

Transpacific trades experienced smaller increases, with volatility on Asia-North America routes rising from about 20% to 30%. While notable, these shifts were less severe than those seen on Asia-Europe services.