condition mean min max ZT0-3 7.847799999999999 7.847799999999999 7.847799999999999 ZT4-7 5.963875 5.963875 5.963875 ZT8-11 7.8744250000000005 7.8744250000000005 7.8744250000000005 ZT12-15 8.778134999999999 8.778134999999999 8.778134999999999 ZT16-19 11.57525 11.57525 11.57525 ZT20-23 8.35566 8.35566 8.35566