condition mean min max ZT0-3 70.620456 70.620456 70.620456 ZT4-7 64.6405685 64.6405685 64.6405685 ZT8-11 87.44035249999999 87.44035249999999 87.44035249999999 ZT12-15 84.664827 84.664827 84.664827 ZT16-19 73.321358 73.321358 73.321358 ZT20-23 82.182143 82.182143 82.182143