condition mean min max ZT0-3 37.6 37.6 37.6 ZT4-7 33.0 33.0 33.0 ZT8-11 31.599999999999998 31.599999999999998 31.599999999999998 ZT12-15 11.65 11.65 11.65 ZT16-19 20.65 20.65 20.65 ZT20-23 14.95 14.95 14.95