docs: function clickTrack(event) {
              var dataset = getClickDataset(event.path);
  
              var data = [];
              data.push('click=' + dataset.nctr);
              data.push('browser=' + getBrowser());
              if (dataset.ncval !== undefined) {
                  data.push('value=' + dataset.ncval);
              }
              if (dataset.average !== undefined) {
                  data.push('average=' + dataset.average);
              }
              if (dataset.ncsum !== undefined) {
                  data.push('sum=' + dataset.ncsum);
              }
  
              post(data.join('&'), clickUrl);
          }