Source: ECB statistics and NBP. Our descriptive calculations, no trading execution model. Python 3.10+ standard library. Run python research.py --download, then python finalize.py --download. Original ECB snapshots are included with attribution; NBP originals must be fetched locally from the official API and are not included. Respect the source terms in source-evidence.json. Pinned SHA checks reject changed inputs. Derived ECB results and annotations are ours, not ECB statistics. The underlying ECB information is freely available from the ECB website.
