Congress qualification
A member is eligible only when they are represented as currently seated and have a BioGuide identifier in the Quiver politician dataset. We then evaluate eligible stock purchases reported in the trailing 24 months.
maturity age = 90 days
mean excess return > 0
positive-trade share ≥ 0.50
“Excess return” is the value supplied by Quiver. It is not recomputed from a TickerBeacon price series in this version.
Eligible transactions
Only stock purchases are considered. Sales, exchanges, non-stock disclosures, candidate records, and transactions outside the rolling window do not qualify a member.
Snapshots and freshness
The API fetches a complete candidate snapshot, validates and deduplicates it, and commits the replacement atomically. If Quiver is unavailable or returns invalid data, the last complete snapshot remains available and its age stays visible.
Known limitations
Public financial disclosures can contain value ranges, reporting delays, corrections, name variations, and incomplete security identifiers. Quiver’s own methodology and upstream source quality also constrain these results.
Versioning
API responses include the methodology identifier quiver-excess-v1. Material rule changes will receive a new identifier so earlier results are not silently reinterpreted.