condition mean min max ZT0-3 2.35 2.35 2.35 ZT4-7 5.9 5.9 5.9 ZT8-11 15.899999999999999 15.899999999999999 15.899999999999999 ZT12-15 16.799999999999997 16.799999999999997 16.799999999999997 ZT16-19 10.0 10.0 10.0 ZT20-23 10.9 10.9 10.9