condition mean min max ZT0-3 21.993100000000002 21.993100000000002 21.993100000000002 ZT4-7 21.704099999999997 21.704099999999997 21.704099999999997 ZT8-11 27.41535 27.41535 27.41535 ZT12-15 24.831049999999998 24.831049999999998 24.831049999999998 ZT16-19 28.9966 28.9966 28.9966 ZT20-23 23.2569 23.2569 23.2569