Exponential keyframes for Z position?

Hi everybody,

I came across a situation today where I was animating an object's Z position exponentially (i.e from a value of 40000 to -75 without it jumping in my face in the last second). I ended up just dragging the keyframe handles in the graph editor to smooth out the animation, but was wondering whether any of you knew of a way to have AE automatically create the position keyframes for you. My immediate thought was that you could create a null and give its scale properties the same numeric values as the Z position property, and then either link or duplicate the exponential scaling results. However, copying and pasting different types of data (scale vs position) won't work, so I was wondering whether any of you had any tricks up your sleeve for another workaround.

Thanks in advance!