condition mean min max ZT0-3 2.0616849999999998 1.98933 2.1340399999999997 ZT4-7 3.52255 3.52255 3.52255 ZT8-11 3.25601 3.25601 3.25601 ZT12-15 0 0 0 ZT16-19 2.99841 2.99841 2.99841 ZT20-23 2.92607 2.92607 2.92607