If you want to add a further metric to a Grid, you can easily do so by selecting the metric you want, and adding it to the "Metric" area while editing your Grid.

By using the example from the previous article, where we added the "% Score" to the Metric, we can drag and drop the "No. of Scores" metric to add to the Grid we have already created:

Once you have selected the "No. of Scores" and added it to "Metrics" you will see that the Grid you have created will have changed to reflect what Metrics and Attributes you have added:

If you want to remove any of these Metrics or Attributes, you can simply right-click and remove.