condition mean min max ZT0-3 67.665276 67.665276 67.665276 ZT4-7 60.491805 60.491805 60.491805 ZT8-11 49.235479 49.235479 49.235479 ZT12-15 47.9097715 47.9097715 47.9097715 ZT16-19 56.7784 56.7784 56.7784 ZT20-23 64.5905345 64.5905345 64.5905345