condition mean min max ZT0-3 36.119749999999996 33.36915 38.87035 ZT4-7 42.613749999999996 42.613749999999996 42.613749999999996 ZT8-11 26.92585 26.92585 26.92585 ZT12-15 0 0 0 ZT16-19 34.4212 34.4212 34.4212 ZT20-23 35.1463 35.1463 35.1463