condition mean min max ZT0-3 1.4560499999999998 1.4560499999999998 1.4560499999999998 ZT4-7 0.7641125 0.7641125 0.7641125 ZT8-11 1.323345 1.323345 1.323345 ZT12-15 2.3661849999999998 2.3661849999999998 2.3661849999999998 ZT16-19 2.87723 2.87723 2.87723 ZT20-23 2.077475 2.077475 2.077475