Anti-dive and Anti-squat
Anti-dive and Anti-squat are expressed in terms of percentage and refer to the front diving under braking and the rear squatting under acceleration. They can be thought of as the counterparts for braking and acceleration as Roll Center Height is to cornering. The main reason for the difference is due to the different design goals between front and rear suspension, whereas suspension is usually symmetrical between the left and right of the vehicle.
Anti-dive and Anti-squat percentage are always calculated with respect to a vertical plane that intersects the vehicle's Center of Gravity.
Consider Anti-dive. Locate the front Centers of the suspension from the vehicle's side view. Draw a line from the tire contact patch through the Instant Center: this is the tire force vector. Now draw a line straight down from the vehicle's center of gravity. The Anti-dive is the ratio between the height of where the tire force vector crosses the center of gravity plane expressed as a percentage.
An Anti-dive ratio of 50% would mean the force vector under braking crosses half way between the ground and the center of gravity.