Methodology

Contribution window

We sum PAC contributions from the N quarters immediately before a roll-call vote date. N is defined per evidence case based on the relevant election cycle.

Delta formula

((current − prior) / prior) × 100, rounded to two decimal places. Returns no result if the prior period had zero or negative contributions.

What “industry” means

Each contribution is assigned one canonical industry key using a fixed priority chain: editor overrides first, then the OpenSecrets sector crosswalk when a RealCode is available, then deterministic employer/occupation rules (for example, retired and not employed), then an offline LLM pass over residual public FEC employer fields. Low confidence or non-sector outputs stay unmapped rather than inventing a sector. LLM results are cached by input hash so re-runs are reproducible.

Limitations

Correlation only, not causation. Covers itemized FEC individual contributions linked to candidates in our politician roster; does not include dark money or unitemized totals. Industry labels are derived classifications of public FEC fields, not donor self-reported sectors. One election cycle per evidence case.