diff --git a/src/pool.js b/src/pool.js
index c113e96..fd3eb9a 100644
--- a/src/pool.js
+++ b/src/pool.js
@@ -1,6 +1,8 @@
 import { XMR_PORT } from "./constants.js";
 import { isFiniteNumber } from "./format.js";
 
+const coinSymbolCountsCache = new WeakMap();
+
 function byPort(values, port) {
   if (!values || typeof values !== "object") return undefined;
   if (Object.hasOwn(values, port)) return values[port];
@@ -93,13 +95,26 @@ export function coinRouteId(poolStats = {}, port) {
 
 function hasDuplicateCoinSymbol(poolStats = {}, symbol) {
   const wanted = coinRouteSlug(symbol);
-  let count = 0;
+  if (!wanted) return false;
+  return getCoinSymbolCounts(poolStats).get(wanted) > 1;
+}
+
+function getCoinSymbolCounts(poolStats = {}) {
+  const coinsRef = poolStats?.coins;
+  if (!coinsRef || typeof coinsRef !== "object") return new Map();
+
+  const cached = coinSymbolCountsCache.get(poolStats);
+  if (cached?.coinsRef === coinsRef) return cached.counts;
+
+  const counts = new Map();
   for (const coin of coinStatsRows(poolStats)) {
     const metadata = coinMetadata(poolStats, coin.p) || {};
-    if (coinRouteSlug(metadata.symbol || coin.s) === wanted) count += 1;
-    if (count > 1) return true;
+    const key = coinRouteSlug(metadata.symbol || coin.s);
+    if (!key) continue;
+    counts.set(key, (counts.get(key) || 0) + 1);
   }
-  return false;
+  coinSymbolCountsCache.set(poolStats, { coinsRef, counts });
+  return counts;
 }
 
 function routeLabel(value) {