Port Window: a verification checklist
A useful result is one you can explain, reproduce, and challenge.
Before entering data
Check the units, dates, and scope of each input. Keep the original record or measurement, including its source and version. Do not combine figures from incompatible periods, editions, products, or measurement conventions. Unknown values should remain unknown rather than being replaced with convenient estimates.
Before making a decision
Verify ship time, port time, all-aboard instructions, and live transport conditions directly. This tool does not guarantee a safe return. Compare the output with a small hand-worked example. Change the most uncertain inputs and check whether the decision changes. A precise-looking number can still depend on an uncertain assumption.
Before sharing a report
Review the output for personal or confidential information. Local saves remain on this browser and can be deleted in Saved plans. CSV and JSON exports are ordinary files; protect them accordingly. Include source dates, assumptions, and unresolved issues when handing the result to someone else.