condition mean min max ZT0-3 16.93776991 12.14668492 21.7288549 ZT4-7 14.00597520775 12.7909086415 15.221041774 ZT8-11 17.7827615325 14.364053145 21.20146992 ZT12-15 38.5742426275 25.759030225 51.38945503 ZT16-19 42.864344375 42.432594585000004 43.296094165 ZT20-23 34.3448618625 27.9963746 40.693349125