Spline area series, like area series, are used to clearly emphasize change in values. However, spline area series help «smooth» individual lines that connect data points. In this example, you can switch between the spline area, stacked spline area and full-stacked spline area series types. Stacked spline area series help visualize multiple series and compare the manner in which each series contributes to the total aggregate value for specific arguments. Full-stacked spline area series help compare the percentage value of multiple spline area series for each argument.