condition mean min max ZT0-3 0.747345 0.747345 0.747345 ZT4-7 0.26732849999999997 0.26732849999999997 0.26732849999999997 ZT8-11 0.20880300000000002 0.20880300000000002 0.20880300000000002 ZT12-15 0.4955535 0.4955535 0.4955535 ZT16-19 1.1608100000000001 1.1608100000000001 1.1608100000000001 ZT20-23 0.948002 0.948002 0.948002