Number of Portuguese ships moving between Europe and Asia 1500-1635
When this trade went uninterrupted, the average duration of journeys from Lisbon to Cochin (present-day Kochi, southwest India) took 5.75 months, and return journeys took 6.5 months. Additionally, ships were also built larger over time to maximize carrying capacity and durability, and average carrying capacities rose from around 300 tons in the 1500s, to 1,000 tons in the 1600s*. The increased carrying capacity also meant that trade levels could be maintained despite the average annual number of journeys decreasing.