condition mean min max ZT0-3 30.724275 29.5027 31.94585 ZT4-7 27.8596 27.8596 27.8596 ZT8-11 23.2446 23.2446 23.2446 ZT12-15 0 0 0 ZT16-19 40.51985 40.51985 40.51985 ZT20-23 36.550799999999995 36.550799999999995 36.550799999999995