condition mean min max ZT0-3 83.9 83.9 83.9 ZT4-7 73.2 73.2 73.2 ZT8-11 61.699999999999996 61.699999999999996 61.699999999999996 ZT12-15 71.0 71.0 71.0 ZT16-19 69.35 69.35 69.35 ZT20-23 79.05 79.05 79.05