condition mean min max ZT0-3 3.728655 3.2745949999999997 4.182715 ZT4-7 2.43866 2.43866 2.43866 ZT8-11 3.825915 3.825915 3.825915 ZT12-15 0 0 0 ZT16-19 5.31445 5.31445 5.31445 ZT20-23 3.097875 3.097875 3.097875