diff --git a/benchmarking/src/components/chart.js b/benchmarking/src/components/chart.js
index 94c81c0..d1aa514 100644
--- a/benchmarking/src/components/chart.js
+++ b/benchmarking/src/components/chart.js
@@ -37,16 +37,16 @@ class WasmVsJsChart extends React.Component {
       values: 'mean'
     }
   }
-  convertDataToHz() {
-    let datasets = this.props.data.datasets
+  convertDataToHz(data) {
+    let datasets = data.datasets
     for (let dataset of datasets.filter(d => d.label !== 'numberOfNodes')) {
       dataset.data = dataset.data.map(mean => 1000 / mean)
     }
   }
   render() {
-    let data = this.props.data
+    let data = JSON.parse(JSON.stringify(this.props.data)) // deep copy
     let options = genOptions('Wasm vs. JavaScript', false, this.state.scaleY)
-    if (this.state.values === 'hz') this.convertDataToHz()
+    if (this.state.values === 'hz') this.convertDataToHz(data)
     return (
       <>
         <Line height={400} width={400} data={data} options={options} />