condition mean min max ZT0-3 3.492355 2.8906799999999997 4.09403 ZT4-7 2.13314 2.13314 2.13314 ZT8-11 3.57442 3.57442 3.57442 ZT12-15 0 0 0 ZT16-19 4.830055 4.830055 4.830055 ZT20-23 3.7016549999999997 3.7016549999999997 3.7016549999999997