
Median and 90th-percentile time in port per harbour — the turnaround metric (not a single average, but the full dwell distribution).
Across the 60 well-sampled ports, half of all calls clear in about 13 h — but the distribution is what bites: at Dordrecht the slowest tenth run past 4.4 d, 8.0× its 13 h median, the most stretched tail on the board. 39 ports carry a P90 at least 3× their median — where a berth that usually turns in hours can hold a ship for days.
Each harbour's typical call (the median dot) and the reach of its slowest tenth (the amber P90 tail). The longer the amber, the less predictable the berth — a call that usually turns in hours can still become a multi-day hold.
Turnaround = arrival→departure time at each port from detected port calls. Ports ranked by completed-call volume; median and p90 over completed calls only (open calls — vessels still in port — are counted separately). Indicative and improving as coverage deepens. The 60 busiest ports are listed, between them 39,432 completed calls; 128,682 completed calls have been detected across the covered network.