condition mean min max ZT0-3 4.681514999999999 4.382865 4.9801649999999995 ZT4-7 6.947785 6.947785 6.947785 ZT8-11 4.92726 4.92726 4.92726 ZT12-15 0 0 0 ZT16-19 6.54831 6.54831 6.54831 ZT20-23 5.717525 5.717525 5.717525