are you talking about the distance from the low e to the high e. or
in other terms, the bass side to the treble side. or in another term. the nut width?
possibly the surface area of the bass side to the treble?
i think thats what your asking. and.... im not sure honestly. if you would like i can measure my jag for you but i can garentee that it changes the closer to the bridge you get.