The Graph series can share existing category groups, series groups and coordinate systems or you can create those from scratch.
To add new series follow these steps:
Open Series collection editor and Add the desired series - Area, Bar or Line.
Set the CategoryGroup to an existing category group or create a new one from scratch.
Set the SeriesGroup to an existing series group or create a new one from scratch.
Set the CoordinateSystem to an existing coordinate system or create a new one.
Set X, Y or both to an expression, depending on which scale is numerical.
For range series set X0 or Y0 properties.