Should you suppress 0% values in Gmail spam identifier API data?

Feedback-ID: promo42:segment7:welcome:espname

function classify(row) {
  if (!row.apiResultPresent) return "missing";
  if (row.rate == null) return "missing_value";
  if (!Number.isFinite(row.rate) || row.rate < 0) {
    return "invalid_value";
  }
  // Date checks use validated UTC YYYY-MM-DD strings.
  if (!row.dateMappingValid) return "invalid_date_mapping";
  if (row.date < row.firstSendDate) return "invalid_pre_send";
  if (row.sourceConflict) return "provisional_conflict";
  if (row.rate > 0) return "observed";
  if (!row.gmailTrafficKnown || !(row.confirmationPulls >= 1)) {
    return "provisional_zero";
  }
  return "confirmed_zero"; // Internal validation label only.
}

// DAILY query only. metricDefinitionsByName maps each request
// metric name to its full definition, including the identifier filter.
const definition = metricDefinitionsByName.get(stat.metric);
const date = stat.date ? toDate(stat.date) : null;
if (!definition || !date) throw new Error("Unexpected metric or date");

// Example for a numeric rate returned as doubleValue.
// Handle a different documented value type explicitly; never coerce it.
const rawRate = stat.value?.doubleValue;
const valid = Number.isFinite(rawRate) && rawRate >= 0;
const key = JSON.stringify([
  apiVersion, domain, definition, aggregationGranularity, date
]);
observations.set(key, {
  value: valid ? rawRate : null,
  state: rawRate == null ? "missing_value" :
    valid ? "unclassified" : "invalid_value",
  apiResultPresent: true,
  pulledAt,
  raw: stat
});

// Numeric 0 survives. Absent dates stay missing, never { value: 0 }.
// Store each pull separately so later queries do not erase history.