condition mean min max ZT0-3 4.53271 3.059825 6.005595 ZT4-7 5.32862 5.32862 5.32862 ZT8-11 9.704429999999999 9.704429999999999 9.704429999999999 ZT12-15 0 0 0 ZT16-19 7.76689 7.76689 7.76689 ZT20-23 5.904685000000001 5.904685000000001 5.904685000000001