The "Visit Panel Summary" shows the number of visits and visitors by region. Note that the time stamp here is UTC as its possible that the region crosses more than one time zone.

Sample Query containing all fields:

query { 
  supplemental_patterns (
    region:"IL"
    iso_country_code: "US"
    date:"2021-09-20"
  ) {
    visit_panel_summary {
      starting_day
      starting_month
      starting_year
      region
      iso_country_code
      num_visits
      num_unique_visitors
    }
  }
}
{
  "data": {
    "supplemental_patterns": {
      "visit_panel_summary": {
        "starting_day": 20,
        "starting_month": 9,
        "starting_year": 2021,
        "region": "il",
        "iso_country_code": "US",
        "num_visits": 9822096,
        "num_unique_visitors": 984769
      }
    }
  },
  "extensions": {
    "row_count": 1
  }
}