condition mean min max ZT0-3 36.849999999999994 36.849999999999994 36.849999999999994 ZT4-7 23.5 23.5 23.5 ZT8-11 4.75 4.75 4.75 ZT12-15 34.45 34.45 34.45 ZT16-19 52.949999999999996 52.949999999999996 52.949999999999996 ZT20-23 20.85 20.85 20.85