**Type:** Categorical (string) - **Categories:** `M` (man), `F` (woman), `NB` (nonbinary), `Other` - **Distribution (approximate):** M ≈ 52%, F ≈ 44%, NB ≈ 3%, Other ≈ 1% - **Description:** User's self-reported gender identity. - **How generated:** Probabilities calibrated to app demographic surveys