condition mean min max ZT0-3 30.200000000000003 30.200000000000003 30.200000000000003 ZT4-7 27.8 27.8 27.8 ZT8-11 21.849999999999998 21.849999999999998 21.849999999999998 ZT12-15 29.95 29.95 29.95 ZT16-19 18.55 18.55 18.55 ZT20-23 7.45 7.45 7.45