The basic data roles
for a line chart are categories and measures. You can assign one category
only, and the values of the category are plotted on the category axis.
You can assign many measures, and the measure values are plotted on
the response axis.
In addition to the basic
data roles, you can assign additional roles:
Grouping
groups the data according
to the values of the category data item that you assign. A separate
line is created for each value.
Note: Grouping is not available
if you assign multiple measures to the visualization.
Horizontal series
creates a horizontal
series of charts for each value of the category data item that you
assign.
Vertical series
creates a vertical
series of charts for each value of the category data item that you
assign.