condition mean min max ZT0-3 2.6946725 2.3788549999999997 3.01049 ZT4-7 4.27589 4.27589 4.27589 ZT8-11 6.20298 6.20298 6.20298 ZT12-15 0 0 0 ZT16-19 6.7709 6.7709 6.7709 ZT20-23 5.986825 5.986825 5.986825