Even scaling and Offsetting

This might seem like a weird question but I have this object below

Attachment 73859

Basically I have 50 frames of animation and I need to offset the outer line in by the same amount on each frame.I tried doing each by hand and after hours some of the thickness differences gave some parts a jittery look.If I could just offset each by the same amount it would be perfect.

So I guess my question is , is there a way to do this easily by offsetting? If anyone could help me out I would greatly appreciate it.

Thanks
Justin