condition mean min max ZT0-3 27.339838333333333 9.480665 37.16125 ZT4-7 23.604999999999997 23.604999999999997 23.604999999999997 ZT8-11 18.8412 18.8412 18.8412 ZT12-15 25.450375 12.66305 38.237700000000004 ZT16-19 53.42005 53.42005 53.42005 ZT20-23 55.0373 55.0373 55.0373