# Changes from the source lists

- NGSL 1.2 and BSL 1.2 merged into one list keyed by lowercase headword; each entry keeps its rank in each
  source list (`ngsl_rank`, `bsl_rank`).
- Word forms taken from the "lemmatized for teaching" files, lowercased, duplicates removed.
- Frequency statistics other than rank (SFI, U, bands) are not included.