condition mean min max ZT0-3 1.3901976666666667 0.9464330000000001 1.720605 ZT4-7 0.570578 0.570578 0.570578 ZT8-11 0.252039 0.252039 0.252039 ZT12-15 0.314374 0.17503000000000002 0.45371799999999995 ZT16-19 0.0 0.0 0.0 ZT20-23 0.183232 0.183232 0.183232