Seaborne vessel traffic via the Red Sea has dropped sharply since Iran-backed Houthi rebels began attacks on shipping in November last year. But some ships are continuing to run the gauntlet of missiles and drones, despite rising insurance costs and risks to the safety of crew members. Reporting by Laurence Walker, Deputy Editor-in-Chief, Montel. Contributors: Burak Cetinok, Head of research, Arrow Shipbroking Group; Derek Steel, Managing Director, Chartsec.