condition mean min max ZT0-3 19.9839 19.20505 20.76275 ZT4-7 23.722 23.722 23.722 ZT8-11 22.4045 22.4045 22.4045 ZT12-15 0 0 0 ZT16-19 29.65375 29.65375 29.65375 ZT20-23 27.13515 27.13515 27.13515