condition mean min max ZT0-3 7.363528333333333 4.342255 11.825109999999999 ZT4-7 6.396005000000001 6.396005000000001 6.396005000000001 ZT8-11 5.465355 5.465355 5.465355 ZT12-15 4.662635 4.11761 5.20766 ZT16-19 16.25915 16.25915 16.25915 ZT20-23 9.69655 9.69655 9.69655