condition mean min max ZT0-3 2.3304825 1.993475 2.66749 ZT4-7 1.050986 1.050986 1.050986 ZT8-11 0.611823 0.611823 0.611823 ZT12-15 0 0 0 ZT16-19 0.957406 0.957406 0.957406 ZT20-23 1.67314 1.67314 1.67314