diff --git a/src/partition.js b/src/partition.js
index 862b7ca6..269b12d9 100644
--- a/src/partition.js
+++ b/src/partition.js
@@ -5,10 +5,12 @@ export default function() {
   var dx = 1,
       dy = 1,
       padding = 0,
-      round = false;
+      round = false,
+      rootDepth = null;
 
   function partition(root) {
     var n = root.height + 1;
+    rootDepth = root.depth;
     root.x0 =
     root.y0 = padding;
     root.x1 = dx;
@@ -21,7 +23,7 @@ export default function() {
   function positionNode(dy, n) {
     return function(node) {
       if (node.children) {
-        treemapDice(node, node.x0, dy * (node.depth + 1) / n, node.x1, dy * (node.depth + 2) / n);
+        treemapDice(node, node.x0, dy * (node.depth - rootDepth + 1) / n, node.x1, dy * (node.depth - rootDepth + 2) / n);
       }
       var x0 = node.x0,
           y0 = node.y0,