condition mean min max ZT0-3 15.55 15.55 15.55 ZT4-7 31.0 31.0 31.0 ZT8-11 25.25 25.25 25.25 ZT12-15 13.95 13.95 13.95 ZT16-19 32.099999999999994 32.099999999999994 32.099999999999994 ZT20-23 19.25 19.25 19.25