condition mean min max ZT0-3 1.9338474999999997 1.43232 2.4353749999999996 ZT4-7 2.2729 2.2729 2.2729 ZT8-11 2.200315 2.200315 2.200315 ZT12-15 0 0 0 ZT16-19 2.279305 2.279305 2.279305 ZT20-23 1.942195 1.942195 1.942195