condition mean min max ZT0-3 3.82048 2.54471 5.09625 ZT4-7 2.59636 2.59636 2.59636 ZT8-11 2.520985 2.520985 2.520985 ZT12-15 0 0 0 ZT16-19 12.532699999999998 12.532699999999998 12.532699999999998 ZT20-23 15.099899999999998 15.099899999999998 15.099899999999998