For average rigid lenses this is in the range of 0.08 mm to 0.20 mm. As the peripheral curves are made flatter or wider the AEL value increases.
AEL is also referred to as the z-value.
The edge clearance of the lens on the eye does not equal the AEL because the cornea gradually flattens in the periphery. However, a given change in AEL will give the same change in edge lift on the eye.