condition mean min max ZT0-3 19.70715 19.70715 19.70715 ZT4-7 12.97195 12.97195 12.97195 ZT8-11 11.4754 11.4754 11.4754 ZT12-15 15.55235 15.55235 15.55235 ZT16-19 21.5761 21.5761 21.5761 ZT20-23 20.63315 20.63315 20.63315