condition mean min max ZT0-3 2.534205 2.534205 2.534205 ZT4-7 3.809055 3.809055 3.809055 ZT8-11 3.640255 3.640255 3.640255 ZT12-15 2.23766 2.23766 2.23766 ZT16-19 2.014775 2.014775 2.014775 ZT20-23 1.011576 1.011576 1.011576