condition mean min max ZT0-3 0.2603715 0.2603715 0.2603715 ZT4-7 0.1424891 0.1424891 0.1424891 ZT8-11 0.22768 0.22768 0.22768 ZT12-15 0.43545350000000005 0.43545350000000005 0.43545350000000005 ZT16-19 0.38794249999999997 0.38794249999999997 0.38794249999999997 ZT20-23 0.358194 0.358194 0.358194