Comtrade estimation flags

Comtrade estimation flags are boolean columns attached to every record in UN Comtrade Plus. The documented set is isReported, isQtyEstimated, isNetWgtEstimated, isAltQtyEstimated, isGrossWgtEstimated and legacyEstimationFlag, alongside an isAggregate field.

They exist because UNSD supplies data "as reported by national authorities without modification" - and where a component is missing, it is estimated. The flags are the audit trail of which is which.

The practical effect: filtering on isReported lets analysts separate officially reported flows from modeled values. In the cataloged TradeFlow record for electrical machinery and instruments (HS 85/90), the fields sit on bilateral records at reporter x partner x 6-digit HS commodity x flow x period grain, with value, weight and quantity fields alongside.

Trade totals feed market sizing and tariff analysis, and estimated components are not the same evidence as reported ones.

• Unfiltered totals mix two provenance classes. Reported flows come from national authorities; estimated ones fill gaps - summing both without the flags overstates the evidence base.

• Mirror discrepancies get hidden. Reporter and partner figures for the same flow differ; estimation flags tell you which side's number is modeled rather than filed.

• Quantity fields are estimated more often than values. The separate isQtyEstimated, isNetWgtEstimated and isGrossWgtEstimated flags exist precisely because weights and quantities are missing more frequently.

• Legacy compatibility matters. legacyEstimationFlag keeps older pipelines working; a vendor extract that drops it breaks historical comparisons.

1. Confirm all six flags ship. isReported, isQtyEstimated, isNetWgtEstimated, isAltQtyEstimated, isGrossWgtEstimated and legacyEstimationFlag are the documented set; ask which a vendor's extract preserves.

1. Run a reported-only cut. Filter on isReported and compare the total against the unfiltered one - the gap is your modeled exposure.

1. Check quantity flags separately from value. Weights and quantities are estimated independently, so a value-clean record can still carry estimated weight.

1. Verify the grain survived. Bilateral reporter x partner x 6-digit HS x flow x period is the documented structure of the TradeFlow records.

1. Keep attribution. Comtrade data is free with UN Comtrade/UNdata cited as the reference, supplied as contained in the source database without modification by UNSD.

Where to see it in context: electronic equipment instruments data and homefurnishing retail data.

These entries cover the value fields and query interface the flags travel with: - cif fob values — Comtrade Plus trade records carry the trade value expressed three ways: CIF value (cost, insurance and freight), FOB value (free on board) and primaryValue, alongside netWgt, grossWgt and supplementary quantity... - un comtrade plus tradeflow — TradeFlow is UN Comtrade Plus' query interface for the UN's official bilateral merchandise trade statistics, built from reports submitted by national statistical offices.