condition mean min max ZT0-3 30.877666666666666 22.628749999999997 35.3406 ZT4-7 21.890549999999998 21.890549999999998 21.890549999999998 ZT8-11 20.3359 20.3359 20.3359 ZT12-15 33.977225000000004 33.42765 34.5268 ZT16-19 37.80975 37.80975 37.80975 ZT20-23 44.6475 44.6475 44.6475