condition mean min max ZT0-3 29.799999999999997 29.799999999999997 29.799999999999997 ZT4-7 91.6 91.6 91.6 ZT8-11 84.1 84.1 84.1 ZT12-15 61.550000000000004 61.550000000000004 61.550000000000004 ZT16-19 43.55 43.55 43.55 ZT20-23 36.75 36.75 36.75