condition mean min max ZT0-3 1.1737271666666667 0.8427165 1.417535 ZT4-7 0.5882755 0.5882755 0.5882755 ZT8-11 1.305635 1.305635 1.305635 ZT12-15 7.4117175 6.33967 8.483765 ZT16-19 3.992455 3.992455 3.992455 ZT20-23 2.31944 2.31944 2.31944