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You can select a predefined time period, or customize the time period by selecting the start and end dates and times of the time period.
To select the time period of Analytics:
In the Graph Display and Time Control Panel, in the Analytics Time Range textbox, click the down arrow.
A list of selectable time periods opens.From the list of time periods, select a predefined time period (Last hour, Last 3 hours, Last 12 hours, Last 24 hours, Last 3 days, Last 7 days, Last 2 weeks, Last 3 weeks, Last 4 weeks, Last 3 months, Last 6 months, or Last 12 months),or select Custom to specify your own time period (see Customizing the Search Analytics Time Period for a detailed explanation on customizing the time period).
The selected time period is displayed in the textbox, and Analytics runs on this time period.