condition mean min max ZT0-3 3.0992699999999997 2.6831 3.51544 ZT4-7 3.01511 3.01511 3.01511 ZT8-11 2.897765 2.897765 2.897765 ZT12-15 0 0 0 ZT16-19 3.066525 3.066525 3.066525 ZT20-23 2.843655 2.843655 2.843655