diff --git a/.eslintrc b/.eslintrc
index 3a282c9c..bf19fb0c 100644
--- a/.eslintrc
+++ b/.eslintrc
@@ -29,6 +29,7 @@
     "no-magic-numbers": "off",
     "no-undefined": "off",
     "no-inline-comments": "off",
+    "lines-around-comment": "off",
     "indent": ["error", 2, {
       "SwitchCase": 1
     }
diff --git a/src/visits/GraphCard.js b/src/visits/GraphCard.js
index d54c1674..5814739e 100644
--- a/src/visits/GraphCard.js
+++ b/src/visits/GraphCard.js
@@ -54,7 +54,7 @@ const renderGraph = (title, isBarChart, stats, max, highlightedStats) => {
     }
 
     return acc;
-  }, stats));
+  }, { ...stats }));
   const highlightedData = highlightedStats && values({ ...zipObj(labels, labels.map(() => 0)), ...highlightedStats });
 
   const options = {
diff --git a/test/visits/GraphCard.test.js b/test/visits/GraphCard.test.js
index 52975c61..545e8c22 100644
--- a/test/visits/GraphCard.test.js
+++ b/test/visits/GraphCard.test.js
@@ -21,12 +21,14 @@ describe('<GraphCard />', () => {
     expect(doughnut).toHaveLength(1);
     expect(horizontal).toHaveLength(0);
 
-    const { labels, datasets: [{ title, data, backgroundColor, borderColor }] } = doughnut.prop('data');
+    const { labels, datasets } = doughnut.prop('data');
+    const [{ title, data, backgroundColor, borderColor }] = datasets;
     const { legend, scales } = doughnut.prop('options');
 
     expect(title).toEqual('The chart');
     expect(labels).toEqual(keys(stats));
     expect(data).toEqual(values(stats));
+    expect(datasets).toHaveLength(1);
     expect(backgroundColor).toEqual([
       '#97BBCD',
       '#DCDCDC',
@@ -65,4 +67,21 @@ describe('<GraphCard />', () => {
       yAxes: [{ stacked: true }],
     });
   });
+
+  it.each([
+    [{ foo: 23 }, [ 100, 456 ], [ 23, 0 ]],
+    [{ foo: 50 }, [ 73, 456 ], [ 50, 0 ]],
+    [{ bar: 45 }, [ 123, 411 ], [ 0, 45 ]],
+    [{ bar: 20, foo: 13 }, [ 110, 436 ], [ 13, 20 ]],
+    [ undefined, [ 123, 456 ], undefined ],
+  ])('splits highlighted data from regular data', (highlightedStats, expectedData, expectedHighlightedData) => {
+    wrapper = shallow(<GraphCard isBarChart title="The chart" stats={stats} highlightedStats={highlightedStats} />);
+    const horizontal = wrapper.find(HorizontalBar);
+
+    const { datasets: [{ data }, highlightedData ] } = horizontal.prop('data');
+
+    expect(data).toEqual(expectedData);
+    expectedHighlightedData && expect(highlightedData.data).toEqual(expectedHighlightedData);
+    !expectedHighlightedData && expect(highlightedData).toBeUndefined();
+  });
 });