condition mean min max ZT0-3 33.5 33.5 33.5 ZT4-7 39.3 39.3 39.3 ZT8-11 19.0 19.0 19.0 ZT12-15 78.95 78.95 78.95 ZT16-19 37.699999999999996 37.699999999999996 37.699999999999996 ZT20-23 19.2 19.2 19.2