BR-Index — Methodology
Scope. BR-Index is a family of daily scrap benchmarks. Series definitions (symbol/region/material/currency) are listed at /indices/universe. All calculations use UTC; the as-of date equals trade date.
Inputs & Eligibility
- Vendor submissions/quotes meeting onboarding checks.
- Internal reference component derived from related metals (stabilizer only).
- Operational signals (BOL/contract events) where applicable.
Duplicates, stale (>5 business days), obvious errors, or non-arm’s-length prints are excluded.
Calculation (Blended)
index_price = w_vendor * vendor_blend + w_contract * contract_vwap + w_reference * operator_reference
defaults: w_vendor=0.70, w_contract=0.20, w_reference=0.10 (weights renormalize across whatever
components are available for a series; the operator reference is a supplemental input, never dominant)Vendor blend: median of the latest per-vendor quotes (outlier-resistant), k-anonymity ≥3 distinct vendors. Contract VWAP: volume-weighted average of recent executed contracts. Rounding: nearest $0.50 unless a series specifies otherwise.
Outliers & Minimums
- Z-score ±2.5 and IQR fences; down-weight or exclude
- Publish if ≥3 eligible vendors, else fallback reduces vendor weight
Fallbacks & Holidays
Insufficient contributors → clamp vendor weight (e.g., 0.10) and increase reference component. US federal banking holidays: prior business day carries.
Corrections & Restatements
Material input errors may trigger restatement (generally within T+10 business days). Incidents are logged at /indices/incidents.
Governance & Transparency
- Oversight: Index Governance Committee (/governance)
- Change control & notices: /static/indices/changes.json
- Where recorded, authorized operators can inspect run-level lineage at
/indices/runs/{run_id}. Raw input manifests are not public because they may identify counterparties.
Access & Licensing
Public index data: BRidge public index board (data may be delayed or limited). Enterprise/API under license (see Benchmark Terms).