condition mean min max ZT0-3 21.967764 21.967764 21.967764 ZT4-7 17.3989585 17.3989585 17.3989585 ZT8-11 19.776133 19.776133 19.776133 ZT12-15 14.0170395 14.0170395 14.0170395 ZT16-19 19.022244 19.022244 19.022244 ZT20-23 12.477533999999999 12.477533999999999 12.477533999999999