condition mean min max ZT0-3 18.880850000000002 17.8275 19.9342 ZT4-7 12.91165 12.91165 12.91165 ZT8-11 21.83165 21.83165 21.83165 ZT12-15 0 0 0 ZT16-19 25.00845 25.00845 25.00845 ZT20-23 24.7179 24.7179 24.7179