The progress dashboard is meant to inspect your progress over time. Which metrics are improving and which are not? And it makes clear whether you are consistent with your shots. As for all dashboards, at the top you can make a selection of your shot data based on date range, club, filter, and so on.
The four progress chart components each show the progress of a particular metric. You can change that metric by clicking the columns icon. The white line shows the average value of the metric as it changes over time. The light and dark areas contain half and all metric values. The narrower these areas are, the more consistent your shots.
Note that you can always change the progress dashboard if you prefer other component. For this, use the edit icon in the toolbar. You can also change the settings of each component to change the information shown and the look.