condition mean min max ZT0-3 1.43674 1.43674 1.43674 ZT4-7 1.64715 1.64715 1.64715 ZT8-11 3.78546 3.78546 3.78546 ZT12-15 3.40454 3.40454 3.40454 ZT16-19 3.9478549999999997 3.9478549999999997 3.9478549999999997 ZT20-23 1.9868450000000002 1.9868450000000002 1.9868450000000002