Overview

Every day at IST midnight the FE backfill writes one row per state-day to `atlas_intelligence.state_mape_daily` with the metered demand vs the previous day's day-ahead forecast. The /state-mape-history endpoint returns the trailing 30-day MAPE band per state — surfaced on state pages as the 'how accurate is the forecast' card.

Endpoint

GET /api/v1/states/<code>/mape-history?days=30

Sample response

{
  "state_code": "TN",
  "points": [
    {
      "ist_date": "2026-05-25",
      "mape_pct": 4.7,
      "sample_n": 24
    },
    {
      "ist_date": "2026-05-26",
      "mape_pct": 5.1,
      "sample_n": 24
    }
  ]
}

Citation lineage

• Atlas state demand forecast (IEA-427 / IEA-429)
• Metered SLDC demand series