condition mean min max ZT0-3 1.308565 1.308565 1.308565 ZT4-7 0.9634325 0.9634325 0.9634325 ZT8-11 1.47355 1.47355 1.47355 ZT12-15 1.32514 1.32514 1.32514 ZT16-19 2.381535 2.381535 2.381535 ZT20-23 1.4179849999999998 1.4179849999999998 1.4179849999999998