diff --git a/router/router.py b/router/router.py
index 06eeb60..67b49a9 100644
--- a/router/router.py
+++ b/router/router.py
@@ -424,7 +424,7 @@ def performance():
             return jsonify({"models": [], "reasons": [], "agents": [], "summary": {"total_requests": 0}})
 
         def pct(values, p):
-            if not values: return 0
+            if len(values) < 2: return round(values[0], 1) if values else 0
             return round(statistics.quantiles(sorted(values), n=100, method='inclusive')[min(p-1, 98)], 1)
 
         # Per-model stats