Division 3 The lean meat content of the carcase shall be calculated according to the following formula:

the estimated percentage of lean meat in the carcase,

the thickness of muscle on the midline of the split carcase, measured at the shortest distance between the cranial end of the m.gluteus medius and the edge of the canalis vertebralis (in millimetres),

the thickness of the back fat (including rind) on the midline of the split carcase, measured at the narrowest place over the m.gluteus medius muscle (in millimetres).