diff --git a/src/lib/template/dom-repeat.html b/src/lib/template/dom-repeat.html
index dd3d42b9f0..9568efc4dd 100644
--- a/src/lib/template/dom-repeat.html
+++ b/src/lib/template/dom-repeat.html
@@ -315,9 +315,8 @@
       // Simple auto chunkSize throttling algorithm based on feedback loop:
       // measure actual time between frames and scale chunk count by ratio
       // of target/actual frame time
-      var lastChunkTime = this._lastChunkTime;
       var currChunkTime = performance.now();
-      var ratio = this._targetFrameTime / (currChunkTime - lastChunkTime);
+      var ratio = this._targetFrameTime / (currChunkTime - this._lastChunkTime);
       this._chunkCount = Math.round(this._chunkCount * ratio) || 1;
       this._limit += this._chunkCount;
       this._lastChunkTime = currChunkTime;
@@ -668,7 +667,7 @@
       } else {
         inst = this._stampInstance(idx, key);
       }
-      var beforeRow = this._instances[idx + 1 ];
+      var beforeRow = this._instances[idx + 1];
       var beforeNode = beforeRow && !beforeRow.isPlaceholder ? beforeRow._children[0] : this;
       var parentNode = Polymer.dom(this).parentNode;
       Polymer.dom(parentNode).insertBefore(inst.root, beforeNode);