condition mean min max ZT0-3 21.8996 17.1936 26.6056 ZT4-7 19.2528 19.2528 19.2528 ZT8-11 21.874399999999998 21.874399999999998 21.874399999999998 ZT12-15 23.763616666666664 20.918733333333332 26.6085 ZT16-19 28.24 28.24 28.24 ZT20-23 28.6702 28.6702 28.6702