To enable forecasting
for a line chart, select Forecasting on the Roles tab.
Note: To apply forecasting, the
line chart must contain a date or datetime item.
On the Properties tab
for the line chart visualization, you can adjust the number of data
points to predict by using the Duration option.
You can also specify the degree of confidence for the confidence band
by using the Confidence option.
On the Roles tab,
you can add 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.