condition mean min max ZT0-3 4.283837500000001 3.793055 4.7746200000000005 ZT4-7 3.97851 3.97851 3.97851 ZT8-11 3.881885 3.881885 3.881885 ZT12-15 0 0 0 ZT16-19 4.498675 4.498675 4.498675 ZT20-23 4.942304999999999 4.942304999999999 4.942304999999999