condition mean min max ZT0-3 34.826325 31.66895 37.9837 ZT4-7 23.871299999999998 23.871299999999998 23.871299999999998 ZT8-11 22.5134 22.5134 22.5134 ZT12-15 0 0 0 ZT16-19 29.3396 29.3396 29.3396 ZT20-23 30.75425 30.75425 30.75425