condition mean min max ZT0-3 2.8393783333333333 2.4773449999999997 3.35883 ZT4-7 1.6259350000000001 1.6259350000000001 1.6259350000000001 ZT8-11 1.44072 1.44072 1.44072 ZT12-15 1.1456184999999999 0.7576069999999999 1.53363 ZT16-19 0.8734525 0.8734525 0.8734525 ZT20-23 1.66422 1.66422 1.66422