condition mean min max ZT0-3 39.002633333333335 29.058300000000003 44.0925 ZT4-7 20.632849999999998 20.632849999999998 20.632849999999998 ZT8-11 16.626800000000003 16.626800000000003 16.626800000000003 ZT12-15 19.39515 18.10425 20.68605 ZT16-19 20.5593 20.5593 20.5593 ZT20-23 36.4432 36.4432 36.4432