condition mean min max ZT0-3 7.279999999999999 7.279999999999999 7.279999999999999 ZT4-7 6.762777778 6.762777778 6.762777778 ZT8-11 6.297222222 6.297222222 6.297222222 ZT12-15 5.26 5.26 5.26 ZT16-19 4.212222222333334 4.212222222333334 4.212222222333334 ZT20-23 5.125555555666667 5.125555555666667 5.125555555666667