condition mean min max ZT0-3 21.885307 21.885307 21.885307 ZT4-7 25.714196 25.714196 25.714196 ZT8-11 22.553081 22.553081 22.553081 ZT12-15 30.257875 30.257875 30.257875 ZT16-19 25.958934 25.958934 25.958934 ZT20-23 27.4996595 27.4996595 27.4996595