Number of Portuguese ships moving between Europe and Asia 1500-1635

In the first 135 years of Portuguese sea trade with Asia, there were over 900 ship departures from Lisbon to Asia, but fewer than 500 Portuguese arrivals in Lisbon at the end of these journeys. A large share of this difference is due to losses at sea (both through weather and combat), although many of these ships remained overseas in order to protect Portuguese interests, or facilitate trade between the various regions of Asia.

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.