curl --request GET \
  --url https://api.amberflow.io/v1/groups/{group_id}/historical \
  --header 'X-API-Key: <api-key>'

{
  "data": [
    {
      "time": "2024-09-23T12:00:00.000Z",
      "forecast": 100,
      "upward": 90,
      "downward": 10,
      "actual": 100
    }
  ]
}