Linear and proportional measurements. 1, Anterior facial height (AFH; N-Me, mm); 2, posterior facial height (PFH; S-Go, mm); 3, upper anterior facial height (UAFH; N′-ANS′, mm) (N′ means the projection of N on N-perpendicular line, and ANS′ means the projection of ANS on N-perpendicular line); 4, lower anterior facial height (LAFH; ANS′-Me′, mm) (Me′ means the projection of Me on the N-perpendicular line); 5, total facial height (TFH; N′-Me′, mm) (3 + 4); 6, anteroposterior facial height ratio (APFHR; S-Go/N-Me, %) (2:1); and 7, lower facial height ratio (LFHR; ANS′-Me′/N′-Me′, %) (4:5)