condition mean min max ZT0-3 0.807746 0.654239 0.9612529999999999 ZT4-7 3.60187 3.60187 3.60187 ZT8-11 0.364466 0.364466 0.364466 ZT12-15 0 0 0 ZT16-19 2.933935 2.933935 2.933935 ZT20-23 19.8883 19.8883 19.8883