condition mean min max ZT0-3 8.644443444 5.825034043 11.463852845000002 ZT4-7 16.413090845 13.83871576 18.98746593 ZT8-11 23.1438719475 20.727806105 25.55993779 ZT12-15 21.322663730000002 21.05039706 21.594930400000003 ZT16-19 40.99383091 25.133007900000003 56.854653920000004 ZT20-23 157.226497585 119.64095582 194.81203935