ZBrushCentral

decrease/increase draw size WITH stroke

Is there any way to draw a stroke and have the draw size shrink or grow proportional to the stroke length / distance from stroke start.
For example to draw stamps out in increasing or decreasing size, or to carve a layer stroke that tapers as its drawn ?

I know you can do this slightly with the wacom tablets pressure but its way off what I require.

Thanks in advance,

Dan.