diff --git a/horizon/static/horizon/js/horizon.d3piechart.js b/horizon/static/horizon/js/horizon.d3piechart.js
index 816bfd9f43..0d8e0da331 100644
--- a/horizon/static/horizon/js/horizon.d3piechart.js
+++ b/horizon/static/horizon/js/horizon.d3piechart.js
@@ -28,7 +28,7 @@ horizon.d3_pie_chart = {
     self.chart = d3.selectAll(".d3_pie_chart");
 
     for (var i = 0; i < pie_chart_data.length; i++) {
-      used = parseInt(pie_chart_data[i].dataset.used);
+      used = parseInt($(pie_chart_data[i]).data("used"));
       self.data = [{"percentage":used}, {"percentage":100 - used}];
       self.pieChart(i);
     }