condition mean min max ZT0-3 22.192113 22.192113 22.192113 ZT4-7 21.2649255 21.2649255 21.2649255 ZT8-11 19.3866565 19.3866565 19.3866565 ZT12-15 19.4880085 19.4880085 19.4880085 ZT16-19 25.4027995 25.4027995 25.4027995 ZT20-23 24.586489 24.586489 24.586489