condition mean min max ZT0-3 0.0411657 0.0411657 0.0411657 ZT4-7 0.00774075 0.00774075 0.00774075 ZT8-11 0.00756305 0.00756305 0.00756305 ZT12-15 0.01592585 0.01592585 0.01592585 ZT16-19 0.05312013333333333 0.05312013333333333 0.05312013333333333 ZT20-23 0.0160641 0.0160641 0.0160641