Toxins, cultures of micro-organisms (excluding yeasts) and similar products: n.e.c. in item 3002.3

What does thirty years of bilateral trade data tell us about the world market for this product? Who exports it, who buys it, how concentrated is supply, and what are prices doing?

Who produces it, who consumes it

Exporter concentration reflects where productive capacity sits; importer concentration reflects demand. Large asymmetries between these two distributions are the starting point for any analysis of dependency, market power, or gains from trade.

Concentration of supply

The Herfindahl-Hirschman index on exporter shares summarises supply concentration. The 2023 DOJ/FTC Merger Guidelines put the “highly concentrated” threshold at HHI > 1,800 on the 0-10,000 scale, equivalent to HHI > 0.18 on the 0-1 scale used here; the effective number of exporters 1/HHI reads as a count of equally-sized suppliers. That threshold is a U.S. domestic-antitrust benchmark for a single national market , world-trade concentration is not antitrust-actionable, but it is a familiar yardstick and a useful comparative anchor when reading these series. This HS6 carries a Product Complexity Index (Hidalgo & Hausmann 2009, PNAS 106(26): 10570-10575) of 1.26 (rank #2523 of 6,429 products): high-PCI products are exported by few, diversified economies and are therefore informative about where productive capability concentrates.

Supply concentration dynamics

HHI summarises concentration in a single number; concentration ratios expose how that concentration is distributed across the top of the supplier league. CR_k is the combined world-export share of the top-k exporters. Divergence between CR1 and CR5 says the tail is thick (many mid-sized suppliers behind the leader); convergence says the top-1 dominates and the next four are small. Rising CR1 with stable CR5 is the signature of a single-exporter expansion (Saudi Arabia in crude in the 2000s, China in rare earths in the 2010s, Chile in copper).

Concentration of demand

The supplier-side HHI above measures how concentrated production is. The mirror question is how concentrated demand is: does this product sell to many destinations, or is global demand bottlenecked through a few importers? When demand is concentrated, a single importer’s tariff or recession is a first-order shock to world prices and producer revenues. The importer-side HHI is the same Herfindahl (Adelman 1969) computed on import shares; the comparison of the two series identifies products that are concentrated on one side of the market and dispersed on the other (asymmetric market power).

Price dynamics

The ratio of trade value to physical quantity , the unit value , proxies price when the product is reasonably homogeneous (Kravis & Lipsey 1971). Across heterogeneous exporters, within-HS6 dispersion in unit values is the Schott (2004) revealed-quality proxy. Khandelwal (2010) argues unit values and quality are distinct objects and recovers quality structurally from demand residuals; we stay in the Schott register for this chart. The USD/t axis is meaningful only where BACI reports quantity in metric tons; for HS codes measured in pieces, litres, or carats the USD/t reading is a unit-mismatch artefact, so the chart should be read with the HS6 unit-of-quantity in mind.