condition mean min max ZT0-3 7.2414716666666665 3.2443400000000002 13.42815 ZT4-7 14.320999999999998 14.320999999999998 14.320999999999998 ZT8-11 11.8397 11.8397 11.8397 ZT12-15 2.0581050000000003 2.039495 2.076715 ZT16-19 0.9130675 0.9130675 0.9130675 ZT20-23 0.5917365 0.5917365 0.5917365