# MA spine: enrollment per plan x county x month (known counts)

`medicare_semantic.ma_spine_enroll_plan_county_v20261012a` · Medicare Advantage, Part D, Medicaid · status partial

Part of the MA spine (one connected, normalized Medicare Advantage layer: docs/architecture/2026-10-12-ma-spine.md). Built by tools/ma_spine/, rails pass (docs/architecture/ma-spine/STATUS.md). Accepted for the raw door 2026-11-02 (acceptance gate CANDIDATE, reachable, has data, schema captured; Omega's MA enrollment master reads it).

**Grain.** One row per contract-plan x county SSA x month with a published count (MA contracts H/R), market, product, lineage, parent as was / as now. Partitioned by year.

| column | type | meaning |
|---|---|---|
| contract_id | string |  |
| plan_id | string |  |
| county_ssa | string |  |
| county_fips | string |  |
| state | string |  |
| report_month | date |  |
| members | int |  |
| egwp_plan_id | boolean |  |
| market_key | string |  |
| product_type | string |  |
| lineage_id | string |  |
| parent_id_as_was | string |  |
| parent_id_as_now | string |  |
| spine_version | varchar(10) |  |

Query it: `query_substrate` with `SELECT ... FROM medicare_semantic.ma_spine_enroll_plan_county_v20261012a WHERE ... LIMIT 100`; read `describe_data_source("medicare_semantic.ma_spine_enroll_plan_county_v20261012a")` first.