diff --git a/ic-agent/src/agent/http_transport/dynamic_routing/snapshot/latency_based_routing.rs b/ic-agent/src/agent/http_transport/dynamic_routing/snapshot/latency_based_routing.rs
index b509731f..295b24fa 100644
--- a/ic-agent/src/agent/http_transport/dynamic_routing/snapshot/latency_based_routing.rs
+++ b/ic-agent/src/agent/http_transport/dynamic_routing/snapshot/latency_based_routing.rs
@@ -47,8 +47,8 @@ impl NodeWithMetrics {
             node,
             window_size,
             is_healthy: false,
-            latencies: VecDeque::with_capacity(window_size),
-            availabilities: VecDeque::with_capacity(window_size),
+            latencies: VecDeque::with_capacity(window_size + 1),
+            availabilities: VecDeque::with_capacity(window_size + 1),
             score: 0.0,
         }
     }