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    "Flat unit rate (no automatic slabs or TOU).",
    "Currency symbol is $ for display only; enter numeric values in your local currency. No FX conversion.",
    "Meter mode requires current ≥ previous on the same kWh register; otherwise METER_READING_DECREASED.",
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    "negative rate/kWh/standing/days/fee → VALUE_MUST_BE_NON_NEGATIVE",
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    {
      "title": "U.S. Energy Information Administration (EIA)",
      "section": "Residential electricity prices per kWh",
      "url": "https://www.eia.gov/electricity/",
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