condition mean min max ZT0-3 637.704736 637.704736 637.704736 ZT4-7 488.05107699999996 488.05107699999996 488.05107699999996 ZT8-11 560.0733585 560.0733585 560.0733585 ZT12-15 736.078683 736.078683 736.078683 ZT16-19 1191.7481465 1191.7481465 1191.7481465 ZT20-23 1159.5113405 1159.5113405 1159.5113405