condition mean min max ZT0-3 15.055800000000001 15.055800000000001 15.055800000000001 ZT4-7 13.9848 13.9848 13.9848 ZT8-11 8.63406 8.63406 8.63406 ZT12-15 12.601849999999999 12.601849999999999 12.601849999999999 ZT16-19 15.65145 15.65145 15.65145 ZT20-23 15.47545 15.47545 15.47545