condition mean min max ZT0-3 22.246064 22.246064 22.246064 ZT4-7 23.7589115 23.7589115 23.7589115 ZT8-11 22.1611035 22.1611035 22.1611035 ZT12-15 27.7546605 27.7546605 27.7546605 ZT16-19 22.724286 22.724286 22.724286 ZT20-23 24.356121 24.356121 24.356121