condition mean min max ZT0-3 7.83534 7.83534 7.83534 ZT4-7 14.896 14.896 14.896 ZT8-11 2.01927 2.01927 2.01927 ZT12-15 5.737425 5.737425 5.737425 ZT16-19 13.0891 13.0891 13.0891 ZT20-23 17.2072 17.2072 17.2072