condition mean min max ZT0-3 1.8298216666666667 1.62083 1.9414 ZT4-7 1.918095 1.918095 1.918095 ZT8-11 1.75152 1.75152 1.75152 ZT12-15 2.341955 1.775095 2.9088149999999997 ZT16-19 1.479495 1.479495 1.479495 ZT20-23 2.386695 2.386695 2.386695