condition mean min max ZT0-3 5.3884475 4.654605 6.12229 ZT4-7 4.46055 4.46055 4.46055 ZT8-11 7.62477 7.62477 7.62477 ZT12-15 0 0 0 ZT16-19 7.88889 7.88889 7.88889 ZT20-23 7.2765 7.2765 7.2765