Yes! After you create a Grow/Shrink Animation. Select the animation from
the Animation task pane. Click on the arrow to get the pull-down menu
and choose Effect Options. In the pull-down menu that let's you adjust
the percentage of growing or shrinking, you can also select Vertical,
Horizontal, or Both. Both is the default so if you do nothing it will
grow taller and wider. But you can select Horizontal to get wider and
not taller.
