condition mean min max ZT0-3 0.40383183333333333 0.13859149999999998 0.7970895 ZT4-7 0.6049305 0.6049305 0.6049305 ZT8-11 0.43512100000000004 0.43512100000000004 0.43512100000000004 ZT12-15 2.0416825 1.9961849999999999 2.08718 ZT16-19 0.747484 0.747484 0.747484 ZT20-23 0.638795 0.638795 0.638795