condition mean min max ZT0-3 1.0842778333333334 0.88866 1.323305 ZT4-7 0.5772625 0.5772625 0.5772625 ZT8-11 2.495945 2.495945 2.495945 ZT12-15 3.7721999999999998 3.7696249999999996 3.774775 ZT16-19 2.95012 2.95012 2.95012 ZT20-23 2.3397300000000003 2.3397300000000003 2.3397300000000003