TS-GMRI™ — Errata & Corrections
A complete, dated, signed record of every methodology error, data correction, and implementation bug-fix that has affected the TS-GMRI™ family of indices. We document every mistake openly. This is how a benchmark earns trust.
Correction policy (what counts, what we publish)
The TS-GMRI™ family follows the IOSCO Principles for Financial Benchmarks (§11 Methodology Changes, §12 Transition, §13 Errors). Every event below falls into one of three categories:
- Methodology change — a deliberate update to the rules (e.g. adding a constituent, refining weighting). Always issued as a numbered addendum (v1.1, v1.2, ...) with SHA-256 + Bitcoin timestamp before taking effect.
- Implementation bug-fix — code computed values that did not match the published methodology. Published series is retired and backfilled with full disclosure. Underlying rules unchanged.
- Data correction — an upstream source (CoinGecko, LBMA, CFB) revised a value after we ingested it. Snapshot is rebuilt; previous value archived.
What we never do. We never silently overwrite a published index value, never delete prior snapshots, never adjust base date once locked, never alter constituent membership rules retroactively to flatter a chart. Every snapshot from base date 22 June 2026 onward is preserved in data/gmri/history/<date>.json in the public repository.
Materiality threshold. Any error that changes a published index value by more than 0.10 points is disclosed here within 48 hours of identification. Smaller corrections (rounding, typography, link rot) are corrected in place without a separate entry.
Chronological log
ERR-2026-001 · 28 June 2026 · TS-GMRI-EW formula correction
Category: Implementation bug-fix · Severity: Material (26.83-point overstatement) · Affected member: TS-GMRI-EW only · Resolution: Backfilled full 22–28 June series
What happened. The TS-GMRI-EW (equal-weighted) variant was computed by averaging per-constituent market-cap ratios (mcaptoday / mcapbase) instead of per-constituent price ratios (Ptoday / Pbase). On 26–28 June 2026 a single microcap constituent, TGLD (base mcap ≈ US$74,886), underwent a 5.4× supply expansion. Its market-cap ratio jumped to 5.51 while its actual token price moved only +1.46%. Averaged across 18 constituents this contributed +25.05 points to TS-GMRI-EW, pushing the published value to 122.73 on 28 June.
Impact.
| Date | EW (published, retired) | EW (corrected) | Delta |
|---|---|---|---|
| 2026-06-22 | 100.00 | 100.00 | 0.00 (base) |
| 2026-06-23 | 99.72 | 97.72 | −2.00 |
| 2026-06-24 | 99.58 | 97.13 | −2.45 |
| 2026-06-25 | 97.03 | 94.82 | −2.21 |
| 2026-06-26 | 122.26 | 94.50 | −27.76 |
| 2026-06-27 | 124.63 | 96.52 | −28.11 |
| 2026-06-28 | 122.73 | 95.90 | −26.83 |
Root cause. The function computeEW(records) in scripts/gmri-family.js aggregated market-cap ratios. Market-cap is the product of price and circulating supply; on a microcap constituent a supply emission therefore propagated 1:1 into the index return. This violated the published methodology, which defines EW as price return.
Fix. The function now computes EW = (1/N) × Σ (Ptoday / Pbase) × 100, matching S&P 500 Equal Weight, MSCI Equal Weighted and FTSE EW conventions. When a constituent has no price on a snapshot date, a per-constituent mcap-ratio fallback applies. Base prices are stored in data/gmri/base.json alongside base mcap.
Disclosure. See methodology-v1.3-addendum.md (SHA-256 de230770f6afa7fea4fcbafc2a56c5db2f574f32d0fa503a572df5ebb54c8d14, Bitcoin-stamped via OpenTimestamps on 28 June 2026, confirmation pending). Source commit on GitHub: b90b40d. Backfilled snapshots are preserved in data/gmri/history/ with both price_usd and mcap_usd per constituent. Retired EW values are not adjusted within the original snapshots; they were never representative of the underlying methodology and are listed in this errata for full transparency.
Outliers driving the gap.
- TGLD — price +1.46% / mcap +450.91% (5.4× supply expansion)
- GGBR — price −2.86% / mcap +29.19%
Members not affected. Cap-weighted family members (TS-GMRI, TS-GMRI-CAP20, TS-GMRI-AU, TS-GMRI-PRE, TS-GMRI-AG) correctly aggregate via the sum of market caps. They were never miscomputed. No values retired.
Methodology change log
Numbered methodology versions and addenda issued since base date. Each is locked with SHA-256 and (where confirmed) a Bitcoin timestamp via OpenTimestamps. Earlier versions remain downloadable in the historical archive.
| Version | Issued | Scope | SHA-256 (first 16) | OTS |
|---|---|---|---|---|
| v1.0 | 16 June 2026 | Base methodology, family of 16 members, base date 22 June 2026 = 100 | dc8a47bf7f532641 |
confirmed #953968 |
| v1.1.2 | 17 June 2026 | Wrapper dimension + MEQ/ETF/ROY slots (family grows to 19) | f5f1dafe3354ca21 |
confirmed #954027 |
| v1.2 | 22 June 2026 | Series A baseline lock (TS-Total / TS-Hub / TS-Token site composites — out of GMRI scope) | (see addendum) |
submitted, awaiting Bitcoin confirmation |
| v1.3 | 28 June 2026 | TS-GMRI-EW formula correction (this errata, ERR-2026-001) | de230770f6afa7fe |
submitted 28 June 2026, awaiting Bitcoin confirmation |
How to report a suspected error
If you believe a TS-GMRI™ value is wrong, email [email protected] with the date, member, observed value and your reasoning. We respond within 48 hours and, if the report is material, publish a numbered ERR entry above with full disclosure — whether the cause is on our side or upstream.