If you have a previously saved dashboard that you want to use again with some modifications, you can save a copy of the dashboard with a different name and then use the copy as a template for the new dashboard.
In the Dashboards window, double-click the dashboard you want to copy.
Select the Edit button in the upper-right corner of the window to open the dashboard in editing mode.
Select Save in the upper-left corner of the window, then select Save As.
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Enter a new name for the dashboard, then select the Save button.