curl --request GET \
  --url https://api.example.com/api/consumer-prices/v1/list-retailer-price-spreads

{
  "marketCode": "<string>",
  "asOf": "<string>",
  "basketSlug": "<string>",
  "currencyCode": "<string>",
  "retailers": [
    {
      "slug": "<string>",
      "name": "<string>",
      "basketTotal": 123,
      "deltaVsCheapest": 123,
      "deltaVsCheapestPct": 123,
      "itemCount": 123,
      "freshnessMin": 123,
      "currencyCode": "<string>"
    }
  ],
  "spreadPct": 123,
  "upstreamUnavailable": true
}