Data Source
- Database
- BACI International Trade Database (CEPII), derived from UN Comtrade mirror data. Harmonized bilateral trade flows at the HS 6-digit level.
- Product coverage
- HS 6309 — Worn clothing and other worn articles. Includes second-hand garments traded in bulk regardless of quality grade.
- Years available
- 2015–2024 (provisional for the most recent year)
- Value unit
- Current USD (thousands, then converted to display units)
Flow Direction Classification
Countries are classified as North (developed) or South (developing/least-developed) using the UNCTAD Development Status classification, consistent with UNCTAD flagship publications.
- N→S
- Export from a developed economy to a developing economy
- S→N
- Export from a developing economy to a developed economy
- S→S
- Both exporter and importer are developing or least-developed economies
- N→N
- Both exporter and importer are developed economies
Trade Flow Calculation
- Net bilateral flow
- For each country pair (A, B), the net flow equals the larger reported value between A→B and B→A exports. The dominant direction determines the arc direction. This reduces double-counting from mirror reporting in UN Comtrade.
- Arc width
- Scaled proportionally to the net trade value on a square-root scale to prevent large flows from dominating small ones visually.
- Arc curvature
- All arcs curve in a consistent clockwise direction (SVG
sweep-flag = 1). This means eastward flows bend northward and westward flows bend southward, providing a secondary visual cue for flow direction that complements the color encoding.
Display Threshold (Auto Mode)
To avoid visual overload, the map limits the number of displayed arcs to a maximum of 40 at a time.
- Global view
- Minimum threshold: $10 M. Arcs below this value are hidden.
- With country selection
- Floor scales down with selection breadth (1–3 countries: $10 K; 4–10: $100 K; 11–30: $500 K; 31+: $1 M). If the number of arcs above the floor exceeds 40, the threshold is raised to the 40th-highest value.
- Manual thresholds
- Fixed cut-off values ($10 k – $10 M) override the automatic algorithm.
Partner Concentration (HHI)
Shown in the country detail panel when a country is clicked. Measures how much a country’s trade is spread across partners versus concentrated in just a few analogous to asking “does this country trade with everyone, or depend heavily on one partner?”
- Index used
- Herfindahl–Hirschman Index (HHI): the sum of squared partner trade shares, scaled to 0–10 000. A score of 10 000 means 100% of trade goes to a single partner; a score near 0 means trade is evenly spread across many partners.
- Formula
HHI = ∑(sharei²) × 10 000, where sharei is each partner’s fraction of that country’s total bilateral trade value.- Interpretation
-
■ Diversified (0–2 000): trade spread across many partners
■ Moderate (2 000–4 000): some partners dominate but diversification remains
■ Highly concentrated (>4 000): trade heavily dependent on one or two partners
- Threshold note
- These bands are calibrated for international trade dependency analysis. They are deliberately lower than the antitrust thresholds used in competition law (which start at 2 500 for “concentrated markets”), reflecting that even moderate trade concentration poses diversification risks.
- Data scope
- Computed from all net bilateral flows for the selected year, regardless of the display threshold. This ensures the score is not distorted by the map’s visibility filter.
Maritime Route Visualization
- Coverage
- Sea routes are displayed only for trade flows between different UNCTAD regions (Africa, Americas, Asia, Europe, Oceania). Flows within the same region are shown as straight arcs to avoid visual clutter from short intra-regional routes.
- Algorithm
- Routes are computed using the Eurostat searoute algorithm over a navigable sea graph.
- Port selection
- Representative ports are chosen based on UNCTAD Liner Shipping Connectivity Index (LSCI) scores; the highest-ranked port in each country is used as the routing node. For large countries spanning multiple coasts (United States, Canada, Australia), the nearest coast port to the partner country is selected.
- Disclaimer
- Routes are indicative only. They do not represent actual tracked HS 6309 cargo paths, may not reflect the mode of transport used, and should not be used for navigation.
Map Disclaimer
The boundaries and names shown on this map do not imply official endorsement or acceptance by the United Nations. Dotted and dashed lines represent approximate borders for which the final status has not yet been determined. The designation of countries or territories does not imply the expression of any opinion on the part of UNCTAD concerning their legal status.
How to Cite
UNCTAD (2025). Global Second-Hand Clothes Trade Monitor. United Nations Conference on Trade and Development, Geneva.
