condition mean min max ZT0-3 3.947783333333333 3.39199 4.97912 ZT4-7 2.621845 2.621845 2.621845 ZT8-11 0.9055725 0.9055725 0.9055725 ZT12-15 1.9725449999999998 1.64896 2.29613 ZT16-19 0.9870194999999999 0.9870194999999999 0.9870194999999999 ZT20-23 2.498665 2.498665 2.498665