Now we have created the Stage Volume Table we can easily create the Stage Volume Curve with the Data Plotly plugin.
1. Install the Data Plotly plugin form the plugins repository.
2. Click to open the Data Plotly panel.
3. Make sure to choose the Scatter Plot as Plot type and StageVolume as the Layer. The X field is VolAbsKm3 and the Y field is Level.
5. Uncheck Show legend. Set the Plot title to Stage Volume, keep the Legend title blank. Change the X label to Volume (km3) and Y label to Level (m).
You can save the result as a picture using the button.
From the Stage Volume Curve we can see a sharp change at 86.4 m. That's approximately the elevation of the boundary of the pit.