condition mean min max ZT0-3 4.244715 4.244715 4.244715 ZT4-7 1.39634 1.39634 1.39634 ZT8-11 1.642355 1.642355 1.642355 ZT12-15 1.663575 1.663575 1.663575 ZT16-19 1.37788 1.37788 1.37788 ZT20-23 4.415315 4.415315 4.415315