CommodityWatch methodology changelog

The iShares product pages for IAU and SLV migrated to a new Walrus server-rendered component framework in May 2026. The previous parser (relying on div.product-data-item elements) stopped resolving data. The parser now reads from the KeyFundFactsV3 component embedded in the static HTML, which publishes tonnes directly — no calculation required for current and ongoing observations.

The source continues to publish with an inherent T+2 lag (iShares publication schedule, not a pipeline delay). This has not changed.

Historical IAU and SLV data prior to the series start in this system is not available via a programmatic iShares API — the historical performance download requires a browser-authenticated session. When historical observations are backfilled from the iShares manual download, tonnes are derived from reported ounces of metal where available, or from shares outstanding × a per-share ratio extrapolated backwards using each fund's annual expense rate (IAU 0.25%/yr, SLV 0.50%/yr) anchored to a known current observation. The anchor date and ratio are stored in each backfilled observation's provenance note.

Added the PriceWatch-only TimesFM projection pilot. Projections are generated only when the optional projection step runs after PriceWatch data updates, stored as 12M runs in data/commodities.db, and sliced into 1M, 3M, 6M, and 12M preset horizons when requested in the detail chart.

The methodology now identifies TimesFM 2.5 with checkpoint google/timesfm-2.5-200m-pytorch, cadence regularization, 80% interval storage, audit-only run history, and the non-advice warning shown in the UI.