The disk measures the distance from the edge of the dead center circle to the point the disc is touched, in increments of 1 centimeter (0,01 meters).
Because jumpers usually land on their feet, most try to touch the dead center mark with the heel of their shoe.
Based on this score the best half of the remaining skydivers make it to the last and final round.
The heel is poised over the dead center ensuring this will be the first place the skydiver touches the ground.
The world record has been broken in 2013 by a member of the French Parachuting Team, Thomas Jeannerot.