To add forecasting to a line chart, select Forecasting on the Roles tab.
Note: The line chart must contain
a date or datetime data item to apply forecasting.
On the Properties tab for the line chart, you can adjust the number of data values to predict by using
the Duration option. You can specify the degree of confidence for the confidence band by using
the Confidence option.
On the Roles tab, you can add additional measures to the forecast as Underlying factors. The forecasting model evaluates the additional measures to determine whether they
contribute to the accuracy
of the forecast. If the additional measures do not increase the accuracy of the forecast,
then they are not used. If the additional measures do increase the accuracy of the
forecast, then the forecast line is adjusted, and the confidence bands are narrowed.
Note: Underlying factors are available
only if your line chart contains a single measure in the Measures role.