Transform by Number

With all transformation tools, such as Scale, Rotate, and Shear, you can transform manually by dragging the mouse or numerically. Double-click on any transformation tool to get a dialog for a numeric transformation. By default, the reference point for the transformation is the center of the object. But to open the dialog and set a different reference point, press-and-hold the Option key (PC: Alt key) and click in the spot you'd like to use as a reference point.