condition mean min max ZT0-3 20.604488 20.604488 20.604488 ZT4-7 21.0205635 21.0205635 21.0205635 ZT8-11 16.662255000000002 16.662255000000002 16.662255000000002 ZT12-15 37.648581 37.648581 37.648581 ZT16-19 40.835002 40.835002 40.835002 ZT20-23 146.45378399999998 146.45378399999998 146.45378399999998