condition mean min max ZT0-3 3.0730383333333333 2.9022300000000003 3.3538699999999997 ZT4-7 1.272944 1.272944 1.272944 ZT8-11 1.186659 1.186659 1.186659 ZT12-15 2.3524675 1.98799 2.716945 ZT16-19 2.18026 2.18026 2.18026 ZT20-23 1.7279749999999998 1.7279749999999998 1.7279749999999998