shape layer - offset size change?

is it possible to animate size of a shape layer from an offset position?

for example - you need a rounded cube to "grow" up on the Y axis, like you might have on an animated bar chart. Scale does not work as it distorts the rounding, and no matter where the anchor or center axis is located any changes to the size parameter effect the shape in both directions from the center of the shape.

I realize I can do this with masks, I'd just like to keep it cleaner than that. I'd like to animated the points of a shape just like you can with a mask.