condition mean min max ZT0-3 15.388918333333333 9.086755 25.0432 ZT4-7 15.6313 15.6313 15.6313 ZT8-11 37.07495 37.07495 37.07495 ZT12-15 42.374500000000005 38.191100000000006 46.557900000000004 ZT16-19 28.07535 28.07535 28.07535 ZT20-23 14.59345 14.59345 14.59345