Marking Your Data
* To mark a single item:
Click on the item.
* To mark one or more items in a visualization (Lasso & Axis methods):
Click and drag with the mouse to draw a rectangle enclosing the interesting items.
* To add more items to the marked set:
Press and hold Ctrl.
Unmark everything by clicking on an empty area in the visualization.
Note: As an alternative, you can unmark all data by selecting Edit > Marked Rows > Unmark.