condition mean min max ZT0-3 5.754613336249999 4.9376931404999995 6.571533532 ZT4-7 1.4023595257500001 1.1873234625 1.617395589 ZT8-11 1.5600002330000002 1.5239353720000002 1.596065094 ZT12-15 1.1807122952499998 1.032072809 1.3293517814999998 ZT16-19 3.50949666025 2.9921669465 4.0268263740000005 ZT20-23 8.19971029325 7.199416782 9.2000038045