condition mean min max ZT0-3 51.15 51.15 51.15 ZT4-7 38.6 38.6 38.6 ZT8-11 17.099999999999998 17.099999999999998 17.099999999999998 ZT12-15 15.0 15.0 15.0 ZT16-19 21.35 21.35 21.35 ZT20-23 23.75 23.75 23.75