Hold down the Ctrl key and drag graphic objects to make a copy at the new location.

This also applies to annotation objects added for data points in graph.

Note: In older versions, after using annotation tool to add an annotation on a data point in graph, user could use Alt+Drag to move it to a new data point; or use Ctrl+Shift+Drag to make a new annotation to another data point. But it was kind of hidden and different from the usual hotkeys in other software.