Pivot ratio.
Isn’t that the relationship between the movement of the throwout actuator lever to the movement of the clutch pedal?
Like 1/8” at the throwout lever equals 1” at the pedal (like Danny said). Once you figure out the ratio you’ll know two things: 1.) How far the pedal can push the throw out lever for total movement and 2.) where the throw out lever is when the pedal is at rest (adjustable at the throwout lever). The ratio will tell you how close the lever needs to be to touching the throwout to the plate when the pedal is at rest in order to get the plate to release the clutch disk with a “normal” clutch pedal stroke.
I used to adjust hydraulic clutches in buses the same way: Adjust the slave first, so that you’ve got about 1/8” of free play at the throw-out lever, then adjust the pedal end to give you 3/8”-1/2” free play, max, then bleed the circuit. That should get you in the ballpark and final adjustment just brings the pedal and/or slave ends slightly closer in gap at neutral.