condition mean min max ZT0-3 16.2993 15.446449999999999 17.009149999999998 ZT4-7 23.26245 23.26245 23.26245 ZT8-11 20.52095 20.52095 20.52095 ZT12-15 29.21165 28.77285 29.65045 ZT16-19 27.9355 27.9355 27.9355 ZT20-23 23.7269 23.7269 23.7269