You can define when and how measurement statistic values are reset.
CAUTION: Saving changes to the statistics settings causes the historical stats data to be lost.
To change stats settings:
From the Global Configuration section of the navigation pane, select Global Configuration Settings.
The content tree displays a list of global configuration settings.
From the content tree, select the Stats Settings folder.
The Stats Settings page opens in the work area.
Click Modify.
The fields become editable.
Set the Stats Collection Period. When Stats Reset Configuration is set to Interval, specify the time interval after which stats are written to the Policy Management devices from the list. Options are minutes.