Rollovers are injurious crash events, causing a disproportionate amount of Harm. Current rollover metrics, Critical Sliding Velocity, Tilt Table Ratio, etc are based on turning a vehicle onto its side (one ¼ turn). ¼ turn rollovers account for 6.9% of Abbreviated Injury Scale (AIS) 3 to 6 injuries, whereas four ¼ turn rollovers (one full revolution) account for 69.5% of AIS 3 to 6 injuries. This paper proposes a four ¼ turn rollover metric based on vehicle geometry and mass.